Semi-static transmission configuration indicator configuration

ABSTRACT

Methods, systems, and devices for wireless communications are described. A base station may transmit a configuration indicating a transmission configuration indicator (TCI) state switching pattern and a TCI state switching period to a user equipment (UE). The UE may perform TCI state switching according to the TCI state switching pattern and period, and the UE may receive a downlink transmission according to the TCI state switching pattern. The UE may receive a downlink control information (DCI) including an indication of a TCI state for a subsequent TTI. The UE may receive the downlink signal in accordance with both the TCI state switching pattern and the indication in the DCI. The UE may receive a configuration message indicating a first DCI state, receive a DCI indicating a second TCI state for a subsequent TTI, switch to the second TCI state, and receive a downlink signal using the second TCI state.

CROSS REFERENCE

The present application for patent claims the benefit of U.S.Provisional Patent Application No. 62/742,918 by SUN et al., entitled“SEMI-STATIC TRANSMISSION CONFIGURATION INDICATOR CONFIGURATION,” filedOct. 8, 2018, assigned to the assignee hereof, and which is expresslyincorporated by reference herein.

BACKGROUND

The following relates generally to wireless communications, and morespecifically to semi-static transmission configuration indicator (TCI)configuration.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform-spread-OFDM (DFT-S-OFDM). A wireless multiple-accesscommunications system may include a number of base stations or networkaccess nodes, each simultaneously supporting communication for multiplecommunication devices, which may be otherwise known as user equipment(UE).

Wireless communication systems may operate in millimeter wave (mmW)frequency ranges, e.g., 28 GHz, 40 GHz, 60 GHz, etc. Wirelesscommunications at these frequencies may be associated with increasedsignal attenuation (e.g., path loss), which may be influenced by variousfactors, such as temperature, barometric pressure, diffraction, etc. Asa result, signal processing techniques, such as beamforming, may be usedto coherently combine energy and overcome the path losses at thesefrequencies. Due to the increased amount of path loss in mmWcommunication systems, transmissions from the base station and/or the UEmay be beamformed. Moreover, a receiving device may use beamformingtechniques to configure antenna(s) and/or antenna array(s) such thattransmissions are received in a directional manner.

In conventional wireless communications systems, such as a mmW wirelessnetwork, a data transmission (e.g., physical downlink shared channel(PDSCH)) or a control transmission (a physical downlink control channel(PDCCH)), or the like may be transmitted by a base station using a TCIstate (e.g., corresponding to a beamformed transmission) to a UE. The UEmay use information about the TCI state to configure receivers of the UEto receive the beamformed transmission. In some examples, beams may bewholly or partially blocked (e.g., such as by a person walking in frontof the UE, a user switching their grip on the UE, and the like),degrading performance. Changing a TCI state used by the UE in responsemay improve reception performance, but conventional TCI state switchingmay be slow, require undesired overhead, or otherwise be insufficient orinefficient.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support semi-static transmission configurationindicator (TCI) configuration. In some cases, performing TCI stateswitching according to a pattern may support macro-diversity for adownlink transmissions. A base station may send a configuration messageto a user equipment (UE) and the configuration may indicate a TCI stateswitching pattern and a TCI state switching period including a number oftransmission time intervals (TTIs). The TCI state switching pattern mayindicate a TCI for each TTI of the TCI period. The UE may receive theconfiguration (e.g., via radio resource control (RRC) signaling ormedium access control (MAC) control element (CE)) and may perform TCIstate switching based on the TCI pattern (e.g., may adjust one or moreantenna ports or antenna panels to receive a downlink signal based onthe TCI states of the TCI pattern). In some examples, the UE may alsoreceive a downlink control information (DCI) including a grant, and thegrant may indicate resources for a downlink signal across a set ofaggregated TTIs. The UE may receive the downlink signal during theaggregated TTIs, by performing TCI state switching based on the TCIstate pattern. Performing TCI state switching based on the TCI statepattern, instead of waiting to perform TCI state switching until asubsequent aggregated TTI, may improve system latency and efficiency. Insome examples, the DCI may also indicate a TCI state for TTIs locatedmore than a threshold number of TTIs from the TTI in which the DCI isreceived. In such examples, the UE may perform TCI state switching forthe indicated TTI based on the DCI, instead of based on the configuredTCI state pattern. If the UE does not receive another DCI indicating TCIstates for identified TTIs, the UE may revert to performing TCI stateswitching for downlink signals based on the TCI state pattern after anamount of time has passed (e.g., after a preconfigured timer expires).In some cases, the DCI may indicate one or more TCI state for TTIs thatare subsequent to a known offset (e.g., a known number of TTIs), and maynot indicate any TCI states for TTIs that are within the known offset.This may decrease signaling overhead, improving system efficiency.

In some cases, performing TCI state switching based on a received DCImay improve system latency. A UE may receive one or more downlinksignals using a first TCI state (e.g., a first configuration of antennaports or antenna panels for receiving downlink signals) that correspondsto a beam. The UE may receive a configuration message indicating thefirst TCI state (e.g., via RRC signaling) or may be preconfigured with adefault TCI state, or the like. The UE may receive a DCI including adownlink grant indicating resources for a downlink signal. The DCI mayalso indicate a second TCI state for receiving part of the downlinksignal. The UE may receive a first portion of the downlink signal duringone or more TTIs according to the first TCI state. The UE may thenswitch from the first TCI state to the second TCI state to receive thesecond portion of the downlink signal. In some examples, the TCI switchmay occur after a known offset (e.g., a known number of TTIs).Performing TCI state switching within the aggregated TTI may be fasterthan waiting to perform TCI state switching after a subsequentconfiguration message, which may improve system latency. In some cases,the DCI may indicate one or more TCI states for TTIs that are subsequentto the known offset, and may not indicate any TCI states for TTIs thatare within the known offset. This may decrease signaling overhead,improving system efficiency.

A method of wireless communication at a UE is described. The method mayinclude receiving a configuration indicating a TCI state switchingpattern and a TCI state switching period, the TCI state switching periodindicating a number of a set of TTIs, and the TCI state switchingpattern indicating a TCI state for each of the set of TTIs, performing,by the UE, TCI state switching according to the TCI state switchingpattern and the TCI state switching period, and receiving a downlinktransmission during at least one of the set of TTIs of the TCI stateswitching pattern.

An apparatus for wireless communication at a UE is described. Theapparatus may include a processor, memory in electronic communicationwith the processor, and instructions stored in the memory. Theinstructions may be executable by the processor to cause the apparatusto receive a configuration indicating a TCI state switching pattern anda TCI state switching period, the TCI state switching period indicatinga number of a set of TTIs, and the TCI state switching patternindicating a TCI state for each of the set of TTIs, perform, by the UE,TCI state switching according to the TCI state switching pattern and theTCI state switching period, and receive a downlink transmission duringat least one of the set of TTIs of the TCI state switching pattern.

Another apparatus for wireless communication at a UE is described. Theapparatus may include means for receiving a configuration indicating aTCI state switching pattern and a TCI state switching period, the TCIstate switching period indicating a number of a set of TTIs, and the TCIstate switching pattern indicating a TCI state for each of the set ofTTIs, performing, by the UE, TCI state switching according to the TCIstate switching pattern and the TCI state switching period, andreceiving a downlink transmission during at least one of the set of TTIsof the TCI state switching pattern.

A non-transitory computer-readable medium storing code for wirelesscommunication at a UE is described. The code may include instructionsexecutable by a processor to receive a configuration indicating a TCIstate switching pattern and a TCI state switching period, the TCI stateswitching period indicating a number of a set of TTIs, and the TCI stateswitching pattern indicating a TCI state for each of the set of TTIs,perform, by the UE, TCI state switching according to the TCI stateswitching pattern and the TCI state switching period, and receive adownlink transmission during at least one of the set of TTIs of the TCIstate switching pattern.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, according toa first TCI state during a first TTI of the TCI state switching pattern,a DCI signal that includes a grant of resources for the downlinktransmission and an indication to switch, for a second TTI of the TCIstate switching pattern, to a second TCI state different from a TCIstate indicated by the TCI state switching pattern for the second TTI,where.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the downlinktransmission may include operations, features, means, or instructionsfor receiving the downlink transmission according to the grant ofresources during at least the first TTI according to the first TCI stateand during the second TTI according to the second TCI state, where thedownlink transmission may be aggregated over at least the first TTI andthe second TTI.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the downlink transmissionincludes a single-TTI transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the TCI state switchingpattern may include operations, features, means, or instructions forreceiving, using the first antenna port according to the first TCI stateand using the second antenna port according to the second TCI state, thedownlink transmission during at least one of the set of TTIs of the TCIstate switching pattern.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a secondconfiguration indicating a second TCI state switching pattern and asecond TCI state switching period and receiving a downlink controlinformation signal according to the identified second configuration,where the downlink transmission received during the at least one of theset of TTIs of the TCI state switching pattern includes a downlink datatransmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the configurationmay include operations, features, means, or instructions for receivingthe configuration in RRC signaling that indicates the TCI stateswitching pattern and the TCI state switching pattern.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the configuration in the RRCsignaling further includes an indication of an aggregation mode and anindication of a number of TTIs aggregated in a TTI aggregation periodfor the aggregation mode.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, according toa first TCI state during a first TTI of the TCI state switching pattern,a DCI signal that includes an indication to switch, for a second TTI ofthe TCI state switching pattern, to a second TCI state different from aTCI state indicated by the TCI state switching pattern for the secondTTI, performing TCI state switching based on the indication to switch ofthe received DCI signal and reverting, after a time duration, toperforming TCI state switching according to the TCI state switchingpattern.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving a DCI signalthat indicates a TCI state table, identifying a first set of TCI stateentries in the TCI state table that correspond to TTIs that may belocated less than a threshold number of TTIs from the first TTI,identifying a second set of TCI state entries in the TCI state tablethat correspond to TTIs that may be located more than the thresholdnumber of TTIs away from the first TTI and ignoring the first set of TCIstate entries, where performing TCI state switching may be based on theidentified second set of TCI state entries.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving a DCI signalthat indicates a TCI state table and identify one or more TCI stateentries in the TCI state table that correspond to TTIs that may be morethan a threshold number of TTIs from the first TTI, the TCI state tablelacking TCI state entries corresponding to TTIs that may be less thanthe threshold number of TTIs from the first TTI, where performing TCIstate switching may be based on the identified one or more TCI stateentries.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, a number of different TCIstates in the TCI state switching pattern may be equal to a number ofTTIs in the set of TTIs of the TCI state switching period.

A method of wireless communication at a UE is described. The method mayinclude receiving a configuration indicating a first TCI state for theUE to use to receive downlink signals, receiving, in a first TTIaccording to the first TCI state indicated by the receivedconfiguration, a DCI signal indicating a second TCI state, the first TTIbeing one of a set of TTIs aggregated in a TTI aggregation period,switching, responsive to the received DCI signal, to the indicatedsecond TCI state for a second TTI of the set of TTIs aggregated in theTTI aggregation period, and receiving a downlink signal in the secondTTI according to the second TCI state.

An apparatus for wireless communication at a UE is described. Theapparatus may include a processor, memory in electronic communicationwith the processor, and instructions stored in the memory. Theinstructions may be executable by the processor to cause the apparatusto receive a configuration indicating a first TCI state for the UE touse to receive downlink signals, receive, in a first TTI according tothe first TCI state indicated by the received configuration, a DCIsignal indicating a second TCI state, the first TTI being one of a setof TTIs aggregated in a TTI aggregation period, switch, responsive tothe received DCI signal, to the indicated second TCI state for a secondTTI of the set of TTIs aggregated in the TTI aggregation period, andreceive a downlink signal in the second TTI according to the second TCIstate.

Another apparatus for wireless communication at a UE is described. Theapparatus may include means for receiving a configuration indicating afirst TCI state for the UE to use to receive downlink signals,receiving, in a first TTI according to the first TCI state indicated bythe received configuration, a DCI signal indicating a second TCI state,the first TTI being one of a set of TTIs aggregated in a TTI aggregationperiod, switching, responsive to the received DCI signal, to theindicated second TCI state for a second TTI of the set of TTIsaggregated in the TTI aggregation period, and receiving a downlinksignal in the second TTI according to the second TCI state.

A non-transitory computer-readable medium storing code for wirelesscommunication at a UE is described. The code may include instructionsexecutable by a processor to receive a configuration indicating a firstTCI state for the UE to use to receive downlink signals, receive, in afirst TTI according to the first TCI state indicated by the receivedconfiguration, a DCI signal indicating a second TCI state, the first TTIbeing one of a set of TTIs aggregated in a TTI aggregation period,switch, responsive to the received DCI signal, to the indicated secondTCI state for a second TTI of the set of TTIs aggregated in the TTIaggregation period, and receive a downlink signal in the second TTIaccording to the second TCI state.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the received configurationfurther indicates a TCI state switching pattern and a TCI stateswitching period, the TCI state switching period indicating a number ofa set of TTIs, and the TCI state switching pattern indicating a TCIstate for each of the set of TTIs, including the first TCI state for thefirst TTI.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a first setof TCI state entries in a TCI state table that may be indicated by thereceived DCI signal, the first set of TCI state entries corresponding toTTIs that may be located less than a threshold number of TTIs from thefirst TTI, identifying a second set of TCI state entries in the TCIstate table that correspond to TTIs that may be located more than thethreshold number of TTIs away from the first TTI, ignoring the first setof TCI state entries, where and switching to the indicated second TCIstate may be based on the identified second set of TCI state entries.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying one or moreTCI state entries in a TCI state table that may be indicated by thereceived DCI signal, the one or more TCI states corresponding to TTIsthat may be more than a threshold number of TTIs from the first TTI, andthe TCI state table lacks TCI state entries corresponding to TTIs thatmay be less than the threshold number of TTIs from the first TTI, whereand switching to the indicated second TCI state may be based on theidentified one or more TCI state entries.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, receiving the configurationmay include operations, features, means, or instructions for receivingthe configuration in RRC signaling that indicates the first TCI statefor the UE to use to receive downlink signals.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the configuration in the RRCsignaling further includes an indication of an aggregation mode and anindication of a number of TTIs aggregated in the TTI aggregation periodfor the aggregation mode.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for performing, prior toreceiving the DCI signal indicating the second TCI state, TCI stateswitching according to a first TCI state switching pattern, performing,for a predetermined time duration, TCI state switching responsive to thereceived DCI signal and reverting, after the predetermined timeduration, to performing TCI state switching according to the first TCIstate switching pattern based on identifying that a second DCI signalmay have not been received during the predetermined time duration.

A method of wireless communication at a base station is described. Themethod may include identifying a TCI state switching pattern and a TCIstate switching period, the TCI state switching period indicating anumber of a set of TTIs, and the TCI state switching pattern indicatinga TCI state for each of the set of TTIs, transmitting, to a UE, aconfiguration indicating the identified TCI state switching pattern andthe identified TCI state switching period, and transmitting a downlinktransmission to the UE during at least one of the set of TTIs accordingto the TCI state switching pattern and the TCI state switching period.

An apparatus for wireless communication at a base station is described.The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to identify a TCI state switching pattern and a TCI stateswitching period, the TCI state switching period indicating a number ofa set of TTIs, and the TCI state switching pattern indicating a TCIstate for each of the set of TTIs, transmit, to a UE, a configurationindicating the identified TCI state switching pattern and the identifiedTCI state switching period, and transmit a downlink transmission to theUE during at least one of the set of TTIs according to the TCI stateswitching pattern and the TCI state switching period.

Another apparatus for wireless communication at a base station isdescribed. The apparatus may include means for identifying a TCI stateswitching pattern and a TCI state switching period, the TCI stateswitching period indicating a number of a set of TTIs, and the TCI stateswitching pattern indicating a TCI state for each of the set of TTIs,transmitting, to a UE, a configuration indicating the identified TCIstate switching pattern and the identified TCI state switching period,and transmitting a downlink transmission to the UE during at least oneof the set of TTIs according to the TCI state switching pattern and theTCI state switching period.

A non-transitory computer-readable medium storing code for wirelesscommunication at a base station is described. The code may includeinstructions executable by a processor to identify a TCI state switchingpattern and a TCI state switching period, the TCI state switching periodindicating a number of a set of TTIs, and the TCI state switchingpattern indicating a TCI state for each of the set of TTIs, transmit, toa UE, a configuration indicating the identified TCI state switchingpattern and the identified TCI state switching period, and transmit adownlink transmission to the UE during at least one of the set of TTIsaccording to the TCI state switching pattern and the TCI state switchingperiod.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, accordingto a first TCI state during a first TTI of the TCI state switchingpattern, a DCI signal that includes a grant of resources for thedownlink transmission and an indication for the UE to switch, for asecond TTI of the TCI state switching pattern, to a second TCI statedifferent from a TCI state indicated by the TCI state switching patternfor the second TTI, where.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting the downlinktransmission may include operations, features, means, or instructionsfor transmitting the downlink transmission according to the grant ofresources during at least the first TTI according to the first TCI stateand during the second TTI according to the second TCI state, where thedownlink transmission may be aggregated over at least the first TTI andthe second TTI.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the downlink transmissionincludes a single-TTI transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the TCI state switchingpattern includes a first TCI state associated with a first antenna portfor each of the set of TTIs and a second TCI state associated with asecond antenna port for each of the set of TTIs, the UE to receive thedownlink transmission using the first antenna port according to thefirst TCI state and using the second antenna port according to thesecond TCI state, the downlink transmission during at least one of theset of TTIs of the TCI state switching pattern.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a secondconfiguration indicating a second TCI state switching pattern and asecond TCI state switching period, transmitting, to the UE, anindication of the second configuration and transmitting, to the UE, adownlink control information signal according to the identified secondconfiguration, where the downlink transmission transmitted to the UEduring the at least one of the set of TTIs according to the TCI stateswitching pattern and the TCI state switching period includes a downlinkdata transmission.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting theconfiguration may include operations, features, means, or instructionsfor transmitting the configuration in RRC signaling that indicates theTCI state switching pattern and the TCI state switching pattern.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the configuration in the RRCsignaling further includes an indication of an aggregation mode and anindication of a number of TTIs aggregated in a TTI aggregation periodfor the aggregation mode.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, accordingto a first TCI state during a first TTI of the TCI state switchingpattern, a DCI signal that includes an indication for the UE to switch,for a second TTI of the TCI state switching pattern, to a second TCIstate different from a TCI state indicated by the TCI state switchingpattern for the second TTI, and for the UE to revert, after a timeduration, to performing TCI state switching according to the TCI stateswitching pattern.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting a DCIsignal that indicates a TCI state table, the TCI including a first setof TCI state entries that correspond to TTIs that may be located lessthan a threshold number of TTIs from the first TTI, and including asecond set of TCI state entries that correspond to TTIs that may belocated more than the threshold number of TTIs away from the first TTI,the UE to ignore the first set of TCI state entries when performing TCIstate switching based on the identified second set of TCI state entries.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting a DCIsignal that indicates a TCI state table, one or more TCI state entriesin the TCI state table corresponding to TTIs that may be more than athreshold number of TTIs from the first TTI, and the TCI state tablelacking TCI state entries corresponding to TTIs that may be less thanthe threshold number of TTIs from the first TTI.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, a number of different TCIstates in the TCI state switching pattern may be equal to a number ofTTIs in the set of TTIs of the TCI state switching period.

A method of wireless communication at a base station is described. Themethod may include transmitting, to a UE, a configuration indicating afirst TCI state for the UE to use to receive downlink signals,transmitting, in a first TTI according to the first TCI state indicatedby the transmitted configuration, a DCI signal indicating a second TCIstate to which the UE is to switch, responsive to the DCI signal, for asecond TTI of a set of TTIs aggregated in a TTI aggregation period,where the first TTI is one of the set of TTIs aggregated in the TTIaggregation period, and transmitting a downlink signal in the secondTTI.

An apparatus for wireless communication at a base station is described.The apparatus may include a processor, memory in electroniccommunication with the processor, and instructions stored in the memory.The instructions may be executable by the processor to cause theapparatus to transmit, to a UE, a configuration indicating a first TCIstate for the UE to use to receive downlink signals, transmit, in afirst TTI according to the first TCI state indicated by the transmittedconfiguration, a DCI signal indicating a second TCI state to which theUE is to switch, responsive to the DCI signal, for a second TTI of a setof TTIs aggregated in a TTI aggregation period, where the first TTI isone of the set of TTIs aggregated in the TTI aggregation period, andtransmit a downlink signal in the second TTI.

Another apparatus for wireless communication at a base station isdescribed. The apparatus may include means for transmitting, to a UE, aconfiguration indicating a first TCI state for the UE to use to receivedownlink signals, transmitting, in a first TTI according to the firstTCI state indicated by the transmitted configuration, a DCI signalindicating a second TCI state to which the UE is to switch, responsiveto the DCI signal, for a second TTI of a set of TTIs aggregated in a TTIaggregation period, where the first TTI is one of the set of TTIsaggregated in the TTI aggregation period, and transmitting a downlinksignal in the second TTI.

A non-transitory computer-readable medium storing code for wirelesscommunication at a base station is described. The code may includeinstructions executable by a processor to transmit, to a UE, aconfiguration indicating a first TCI state for the UE to use to receivedownlink signals, transmit, in a first TTI according to the first TCIstate indicated by the transmitted configuration, a DCI signalindicating a second TCI state to which the UE is to switch, responsiveto the DCI signal, for a second TTI of a set of TTIs aggregated in a TTIaggregation period, where the first TTI is one of the set of TTIsaggregated in the TTI aggregation period, and transmit a downlink signalin the second TTI.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the transmitted configurationfurther indicates a TCI state switching pattern and a TCI stateswitching period, the TCI state switching period indicating a number ofa set of TTIs, and the TCI state switching pattern indicating a TCIstate for each of the set of TTIs, including the first TCI state for thefirst TTI.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a first setof TCI state entries for a TCI state table, the first set of TCI stateentries corresponding to TTIs that may be located less than a thresholdnumber of TTIs from the first TTI, identifying a second set of TCI stateentries for the TCI state table that correspond to TTIs that may belocated more than the threshold number of TTIs away from the first TTIand transmitting, to the UE, an indication of the TCI state table in theDCI signal, the UE to ignore the first set of TCI state entries whenswitching to the indicated second TCI state based on the second set ofTCI state entries.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying one or moreTCI state entries for a TCI state table, the one or more TCI statescorresponding to TTIs that may be more than a threshold number of TTIsfrom the first TTI, the TCI state table lacking TCI state entriescorresponding to TTIs that may be less than the threshold number of TTIsfrom the first TTI and transmitting, to the UE, an indication of the TCIstate table in the DCI signal.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting theconfiguration may include operations, features, means, or instructionsfor transmitting the configuration in RRC signaling that indicates thefirst TCI state for the UE to use to receive downlink signals.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the configuration in the RRCsignaling further includes an indication of an aggregation mode and anindication of a number of TTIs aggregated in the TTI aggregation periodfor the aggregation mode.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, transmitting theconfiguration further may include operations, features, means, orinstructions for transmitting an indication for the UE to revert, aftera predetermined time duration, to performing TCI state switchingaccording to a first TCI state switching pattern based on identifyingthat a second DCI signal may have not been received during thepredetermined time duration.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports semi-static transmission configuration indicator (TCI)configuration in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure.

FIG. 3 illustrates an example of a TCI state switching scheme thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure.

FIG. 4 illustrates an example of a TCI state switching scheme thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure.

FIG. 5 illustrates an example of a TCI state switching scheme thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure.

FIG. 6 illustrates an example of a TCI state switching scheme thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure.

FIG. 7 illustrates an example of a TCI state switching scheme thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure.

FIG. 8 illustrates an example of a TCI state switching scheme thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure.

FIG. 9 illustrates an example of a TCI state switching scheme thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure.

FIG. 10 illustrates an example of a process flow that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure.

FIG. 11 illustrates an example of a process flow that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure.

FIGS. 12 and 13 show block diagrams of devices that support semi-staticTCI configuration in accordance with aspects of the present disclosure.

FIG. 14 shows a block diagram of a communications manager that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure.

FIG. 15 shows a diagram of a system including a device that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure.

FIGS. 16 and 17 show block diagrams of devices that support semi-staticTCI configuration in accordance with aspects of the present disclosure.

FIG. 18 shows a block diagram of a communications manager that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure.

FIG. 19 shows a diagram of a system including a device that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure.

FIGS. 20 through 25 show flowcharts illustrating methods that supportsemi-static TCI configuration in accordance with aspects of the presentdisclosure.

DETAILED DESCRIPTION

In some examples, a base station and a user equipment (UE) may performwireless communications. In some examples of a wireless communicationsystem the base station and one or more UEs may communicate on one ormore frequency bands (e.g., a first frequency band (FR1) or a secondfrequency band (FR2)). FR1 may refer to a sub 6 GHz band and FR2 mayrefer to a band that is above 6 GHz. The base station and the UE maycommunicate via multiple beamformed transmissions (e.g., multipletransmission configuration indicator (TCI) states) on a frequency band(e.g., FR2). By using multiple TCI states, wireless communications maybe improved by decreasing the impact of one or more blocked channels(e.g., wholly or partially blocked such as by a person walking in frontof the UE, a user switching their grip on the UE, and the like).

In some examples, transmission time interval (TTI) aggregation (e.g.,slot aggregation or mini-slot aggregation) may support macro diversity.For example, a number of TTIs may be aggregated, and different TCIstates may be used for communications in the aggregated TTI. In someexamples, each TTI may use a different TCI state. In other examples,different combination of TCIs states and TTIs of the aggregated TTI(e.g., slot or mini-slot) may be used. A TCI switching point may occurat TTI boundaries, so that a receiving device (e.g., a UE) may receivedownlink signals according to different receiver configurationscorresponding to the different beams (e.g., for the different TCIstates) in different TTIs. A UE may receive an indication to switch TCIstates, or otherwise determine to switch TCI states, but the UE mayrequire some amount of time between receiving such command or makingsuch determining and performing the TCI switching. The time duration maybe referred to as a TCI switching capability window. If a requested TCIswitching point falls within the TCI switching capability window, thenthe UE may be unable to perform the TCI switching as commanded. Forinstance, a UE may require two slots (e.g., TTIs) to receive a PDSCH,decode the received PDSCH, identify a target TCI state for a TTI, andperform the TCI state switch (e.g., a TCI switching capability window oftwo TTIs). In such examples, the UE may receive a DCI including adownlink grant and a TCI state for a set of aggregated TTIs in a firstTTI. Given the TCI switching capability window of two TTIs, the UE willbe unable to perform TCI switching for at least two TTIs following thefirst TTI. If the DCI including TCI states for the first, second, andthird TTIs of the set of aggregated TTIs, the UE may be unable toperform the TCI switching (or receive data transmissions during thoseTTIs).

If the UE does not perform TCI switching during the TCI switchingcapability window, then macro diversity may be decreased. If the UEreceives a cross slot grant where the granted resources are scheduled inTTIs subsequent to the TCI switching capability window (e.g., to allowTCI state switching after the TCI switching capability window), then thedownlink transmission will be delayed, resulting in increased latencyand decreased user experience.

In some examples, a base station may trigger TCI switching via aconfigured (e.g., via RRC signaling or a MAC CE) TCI switching periodand TCI switching pattern. The RRC configured TCI switching pattern mayinclude a pattern of TCI states across a set of TTIs within the TCIswitching period. The TCI switching pattern may be independent from DCIsignaling. The UE may switch between TCI states based on the TCIswitching pattern, regardless of TCI switching indicated in a DCI,without any TCI switching indicated in a DCI, or in combination with TCIswitching indicated in a DCI.

In some examples, the UE may receive an RRC message indicating the TCIswitching pattern and the TCI switching period. During the TCI switchingperiod, the UE may receive any downlink signals according to the TCIswitching pattern. If the UE receives a downlink grant, the UE mayconfigure a TCI state for each TTI of the granted resources according tothe TCI switching pattern. In some cases, the UE may ignore anindication in the DCI of TCI states for TTIs of the granted resources,and may instead perform TCI state switching based on the RRC configuredTCI switching pattern. In some examples, the DCI may not contain anyindication of TCI switching, and the UE may perform TCI state switchingbased on the RRC configured TCI switching pattern.

In some examples, the UE may perform TCI switching based on acombination of the RRC configured TCI switching pattern and TCIswitching indicated in a DCI. For instance, the UE may receive an RRCmessage including the TCI switching pattern for a TCI switching period.The UE may receive a DCI including a downlink grant and a TCI switchingpattern for a set of aggregated TTIs within the TCI switching period. Insome cases, the UE may ignore the DCI configured TCI switching patternfor TCI states within the TCI switching capability window, and mayinstead perform TCI switching according to the RRC configured TCIswitching pattern during the TCI switching capability window. However,following the TCI capability switching window, the UE may perform TCIstate switching based on the DCI configured TCI switching pattern. Insome examples, the DCI configured switching pattern may only include TCIswitching for TTIs outside of the TCI capability switching window. Afterthe DCI configured TCI switching pattern expires (e.g., after expirationof a timer having a known or predetermined time duration), the UE mayrevert to using the RRC configured TCI switching pattern.

In some examples, the RRC configured switching pattern may include afirst portion and a second portion. The first portion may apply to afirst antenna port or panel at the UE (and may be a first TCI switchingpattern), and the second portion may apply to a second antenna port orpanel at the UE (and may be a second TCI switching pattern). The UE mayreceive data transmissions via the first antenna port based on the firstportion (or first pattern), and may receive data transmissions via thesecond antenna port based on the second portion (or second pattern).

In some cases, the UE may receive single TTI (e.g., single slot)communications, and the base station may indicate a change from the RRCconfigured TCI pattern for subsequent TTIs. For example, the basestation may identify a beam (e.g., a TCI state) that has faded orotherwise is no longer preferred. In such examples, the base station maysend a DCI during a TTI that is configured to receive in a preferred TCIstate. The DCI may include a cross-TTI grant for a subsequent TTI thatis outside of the TCI switching capability window, and an indication toswitch a TCI state from the RRC configured TCI pattern (where the TTI isconfigured with the non-preferred TCI state) to a different TCI statefor the TTI.

In some cases, performing TCI state switching within a TTI aggregationbased on a received DCI (instead of waiting for a subsequentconfiguration message) may improve system latency. A UE may receive oneor more downlink signals using a first TCI state that corresponds to afirst beam. The UE may receive a configuration message indicating thefirst TCI state (e.g., via RRC signaling) or may be preconfigured with adefault TCI state, or the like. The UE may receive a DCI including adownlink grant indicating resources for a downlink signal. The DCI mayalso indicate a second TCI state for receiving part of the downlinksignal within the aggregated TTI. The UE may receive a first portion ofthe downlink signal during one or more TTIs according to the first TCIstate. The UE may then switch from the first TCI state to the second TCIstate to receive the second portion of the downlink signal. In someexamples, the TCI switch may occur after a known offset (e.g., a knownnumber of TTIs). Performing TCI state switching within the aggregatedTTI may be faster than waiting to perform TCI state switching after asubsequent configuration message, which may improve system latency. Insome cases, the DCI may indicate one or more TCI state for TTIs that aresubsequent to the known offset, and may not indicate any TCI states forTTIs that are within the known offset. This may decrease signalingoverhead, improving system efficiency.

Particular aspects of the subject matter described herein may beimplemented to realize one or more advantages. The described techniquesmay support improvements in TCI state switching, decreasing signalingoverhead, and improving reliability, among other advantages. As such,supported techniques may include improved network operations and, insome examples, may promote network efficiencies, among other benefits.

Aspects of the disclosure are initially described in the context of awireless communications system. Aspects of the disclosure are furtherillustrated by and described with reference to TCI state switchingschemes, and process flows. Aspects of the disclosure are furtherillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that relate to semi-static TCIconfiguration.

FIG. 1 illustrates an example of a wireless communications system 100that supports semi-static TCI configuration in accordance with aspectsof the present disclosure. The wireless communications system 100includes base stations 105, UEs 115, and a core network 130. In someexamples, the wireless communications system 100 may be a Long TermEvolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pronetwork, or a New Radio (NR) network. In some cases, wirelesscommunications system 100 may support enhanced broadband communications,ultra-reliable (e.g., mission critical) communications, low latencycommunications, or communications with low-cost and low-complexitydevices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation Node B orgiga-nodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up only a portion of the geographic coverage area110, and each sector may be associated with a cell. For example, eachbase station 105 may provide communication coverage for a macro cell, asmall cell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples,half-duplex communications may be performed at a reduced peak rate.Other power conservation techniques for UEs 115 include entering a powersaving “deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1, N2, N3, orother interface). Base stations 105 may communicate with one anotherover backhaul links 134 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105) or indirectly (e.g.,via core network 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, (e.g., in the range of 300 MHz to 300 GHz). Generally,the region from 300 MHz to 3 GHz is known as the ultra-high frequency(UHF) region or decimeter band, since the wavelengths range fromapproximately one decimeter to one meter in length. UHF waves may beblocked or redirected by buildings and environmental features. However,the waves may penetrate structures sufficiently for a macro cell toprovide service to UEs 115 located indoors. Transmission of UHF wavesmay be associated with smaller antennas and shorter range (e.g., lessthan 100 km) compared to transmission using the smaller frequencies andlonger waves of the high frequency (HF) or very high frequency (VHF)portion of the spectrum below 300 MHz.

Wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that can tolerate interference from otherusers.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a CA configurationin conjunction with CCs operating in a licensed band (e.g., LAA).Operations in unlicensed spectrum may include downlink transmissions,uplink transmissions, peer-to-peer transmissions, or a combination ofthese. Duplexing in unlicensed spectrum may be based on frequencydivision duplexing (FDD), time division duplexing (TDD), or acombination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving devices are equipped with one ormore antennas. MIMO communications may employ multipath signalpropagation to increase the spectral efficiency by transmitting orreceiving multiple signals via different spatial layers, which may bereferred to as spatial multiplexing. The multiple signals may, forexample, be transmitted by the transmitting device via differentantennas or different combinations of antennas. Likewise, the multiplesignals may be received by the receiving device via different antennasor different combinations of antennas. Each of the multiple signals maybe referred to as a separate spatial stream, and may carry bitsassociated with the same data stream (e.g., the same codeword) ordifferent data streams. Different spatial layers may be associated withdifferent antenna ports used for channel measurement and reporting. MIMOtechniques include single-user MIMO (SU-MIMO) where multiple spatiallayers are transmitted to the same receiving device, and multiple-userMIMO (MU-MIMO) where multiple spatial layers are transmitted to multipledevices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying amplitude and phase offsets to signals carried via each of theantenna elements associated with the device. The adjustments associatedwith each of the antenna elements may be defined by a beamforming weightset associated with a particular orientation (e.g., with respect to theantenna array of the transmitting device or receiving device, or withrespect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionand/or reception by the base station 105. Some signals, such as datasignals associated with a particular receiving device, may betransmitted by a base station 105 in a single beam direction (e.g., adirection associated with the receiving device, such as a UE 115). Insome examples, the beam direction associated with transmissions along asingle beam direction may be determined based at least in part on asignal that was transmitted in different beam directions. For example, aUE 115 may receive one or more of the signals transmitted by the basestation 105 in different directions, and the UE 115 may report to thebase station 105 an indication of the signal it received with a highestsignal quality, or an otherwise acceptable signal quality. Althoughthese techniques are described with reference to signals transmitted inone or more directions by a base station 105, a UE 115 may employsimilar techniques for transmitting signals multiple times in differentdirections (e.g., for identifying a beam direction for subsequenttransmission or reception by the UE 115), or transmitting a signal in asingle direction (e.g., for transmitting data to a receiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a plurality of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a plurality of antenna elements of anantenna array, any of which may be referred to as “listening” accordingto different receive beams or receive directions. In some examples, areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based at least inpart on listening according to different receive beam directions (e.g.,a beam direction determined to have a highest signal strength, highestsignal-to-noise ratio, or otherwise acceptable signal quality based atleast in part on listening according to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may insome cases perform packet segmentation and reassembly to communicateover logical channels. A Medium Access Control (MAC) layer may performpriority handling and multiplexing of logical channels into transportchannels. The MAC layer may also use hybrid automatic repeat request(HARQ) to provide retransmission at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and a base station 105 or corenetwork 130 supporting radio bearers for user plane data. At thePhysical (PHY) layer, transport channels may be mapped to physicalchannels.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback is one technique of increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., signal-to-noise conditions). Insome cases, a wireless device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period of T_(s)=1/30,720,000 seconds. Time intervals of a communications resource may beorganized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communications system 100, andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communications system100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs).

In some wireless communications systems, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a symbol of a mini-slot or a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communications systems may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an E-UTRA absolute radiofrequency channel number (EARFCN)), and may be positioned according to achannel raster for discovery by UEs 115. Carriers may be downlink oruplink (e.g., in an FDD mode), or be configured to carry downlink anduplink communications (e.g., in a TDD mode). In some examples, signalwaveforms transmitted over a carrier may be made up of multiplesub-carriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency division multiple access (OFDMA) or DFT-s-OFDM).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR,etc.). For example, communications over a carrier may be organizedaccording to TTIs or slots, each of which may include user data as wellas control information or signaling to support decoding the user data. Acarrier may also include dedicated acquisition signaling (e.g.,synchronization signals or system information, etc.) and controlsignaling that coordinates operation for the carrier. In some examples(e.g., in a carrier aggregation configuration), a carrier may also haveacquisition signaling or control signaling that coordinates operationsfor other carriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may contain onesymbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communications system 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth, or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communications system 100 mayinclude base stations 105 and/or UEs 115 that can support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth.

Wireless communications system 100 may support communication with a UE115 on multiple cells or carriers, a feature which may be referred to ascarrier aggregation (CA) or multi-carrier operation. A UE 115 may beconfigured with multiple downlink CCs and one or more uplink CCsaccording to a carrier aggregation configuration. Carrier aggregationmay be used with both FDD and TDD component carriers.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including wider carrier or frequency channel bandwidth, shortersymbol duration, shorter TTI duration, or modified control channelconfiguration. In some cases, an eCC may be associated with a carrieraggregation configuration or a dual connectivity configuration (e.g.,when multiple serving cells have a suboptimal or non-ideal backhaullink). An eCC may also be configured for use in unlicensed spectrum orshared spectrum (e.g., where more than one operator is allowed to usethe spectrum). An eCC characterized by wide carrier bandwidth mayinclude one or more segments that may be utilized by UEs 115 that arenot capable of monitoring the whole carrier bandwidth or are otherwiseconfigured to use a limited carrier bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than otherCCs, which may include use of a reduced symbol duration as compared withsymbol durations of the other CCs. A shorter symbol duration may beassociated with increased spacing between adjacent subcarriers. Adevice, such as a UE 115 or base station 105, utilizing eCCs maytransmit wideband signals (e.g., according to frequency channel orcarrier bandwidths of 20, 40, 60, 80 MHz, etc.) at reduced symboldurations (e.g., 16.67 microseconds). A TTI in eCC may contain one ormultiple symbol periods. In some cases, the TTI duration (that is, thenumber of symbol periods in a TTI) may be variable.

Wireless communications systems such as an NR system may utilize anycombination of licensed, shared, and unlicensed spectrum bands, amongothers. The flexibility of eCC symbol duration and subcarrier spacingmay allow for the use of eCC across multiple spectrums. In someexamples, NR shared spectrum may increase spectrum utilization andspectral efficiency, specifically through dynamic vertical (e.g., acrossthe frequency domain) and horizontal (e.g., across the time domain)sharing of resources.

In some cases, performing TCI state switching according to a pattern maysupport macro-diversity for a downlink transmissions. A base station maysend a configuration message to a UE 115 and the configuration mayindicate a TCI state switching pattern and a TCI state switching periodincluding a number of TTIs. The TCI state switching pattern may indicatea TCI for each TTI of the TCI period. The UE 115 may receive theconfiguration (e.g., via RRC signaling) and may perform TCI stateswitching based on the TCI pattern (e.g., may adjust one or more antennaports or antenna panels to receive a downlink signal based on the TCIstates of the TCI pattern). In some examples, the UE 115 may alsoreceive a DCI including a grant, and the grant may indicate resourcesfor a downlink signal across a set of aggregated TTIs. The UE 115 mayreceive the downlink signal during the aggregated TTIs, by performingTCI state switching based on the TCI state pattern. Performing TCI stateswitching based on the TCI state pattern, instead of waiting to performTCI state switching until a subsequent aggregated TTI, may improvesystem latency and efficiency. In some examples, the DCI may alsoindicate a TCI state for TTIs located more than a threshold number ofTTIs from the TTI in which the DCI is received. In such examples, the UE115 may perform TCI state switching for the indicated TTI based on theDCI, instead of based on the configured TCI state pattern. If the UE 115does not receive another DCI indicating TCI states for identified TTIs,the UE 115 may revert to performing TCI state switching for downlinksignals based on the TCI state pattern after an amount of time haspassed (e.g., after a preconfigured timer expires). In some cases, theDCI may indicate one or more TCI state for TTIs that are subsequent to aknown offset (e.g., a known number of TTIs), and may not indicate anyTCI states for TTIs that are within the known offset. This may decreasesignaling overhead, improving system efficiency.

In some cases, performing TCI state switching based on a received DCImay improve system latency. A UE 115 may receive one or more downlinksignals using a first TCI state (e.g., a first configuration of antennaports or antenna panels for receiving downlink signals) that correspondsto a beam. The UE 115 may receive a configuration message indicating thefirst TCI state (e.g., via RRC signaling) or may be preconfigured with adefault TCI state, or the like. The UE 115 may receive a DCI including adownlink grant indicating resources for a downlink signal. The DCI mayalso indicate a second TCI state for receiving part of the downlinksignal. The UE 115 may receive a first portion of the downlink signalduring one or more TTIs according to the first TCI state. The UE 115 maythen switch from the first TCI state to the second TCI state to receivethe second portion of the downlink signal. In some examples, the TCIswitch may occur after a known offset (e.g., a known number of TTIs).Performing TCI state switching within the aggregated TTI may be fasterthan waiting to perform TCI state switching after a subsequentconfiguration message, which may improve system latency. In some cases,the DCI may indicate one or more TCI state for TTIs that are subsequentto the known offset, and may not indicate any TCI states for TTIs thatare within the known offset. This may decrease signaling overhead,improving system efficiency.

FIG. 2 illustrates an example of a wireless communications system 200that supports semi-static TCI configuration in accordance with aspectsof the present disclosure. In some examples, wireless communicationssystem 200 may implement aspects of wireless communications system 100.In some examples, wireless communications system 200 may represent a 5Gsystem.

Base station 105-a may serve one or more UEs 115 within coverage area110-a. In some examples, base station 105-a and UE 115-a may utilizehighly directional waves (e.g., beams) for communication. For instance,base station 105-a may send one or more signals to UE 115-a via beams210. In some examples, wireless communications system 200 (e.g., a mmWwireless network), may support macro diversity (e.g., signaling usingdifferent TCI states for different TTI, for example where each TTI of anaggregated TTI uses a different TCI state). Communicating using macrodiversity may improve wireless communications where beamformed channelscan be easily blocked (e.g., such as by a person walking in front of theUE, a user switching their grip on the UE, and the like). That is, ifone beam fades, is blocked, suffers interference from another beam, orthe position of UE 115-a changes, communications using macro diversitymay be beneficial because one or more beams may still successfully carrytransmissions.

In conventional wireless communications systems, such as a mmW wirelessnetwork, base station 105-a may send a transmission (e.g., physicaldownlink shared channel (PDSCH)) or a control transmission (a physicaldownlink control channel (PDCCH)), or the like via one or more beams210. In some examples, macro diversity (e.g., signaling using adifferent TCI state for each TTI) may improve wireless communicationswhere beamformed channels can be easily blocked. In some examples, UE115-a and base station 105-a may support TTI aggregation. TTIs may beslots, mini-slots, or the like. Base station 105-a may send a firstportion of a data message on first beam 210-a during a first TTI, asecond portion of a data message on a second beam 210-b during a secondTTI, a third portion of a data message on third beam 210-c during athird TTI, a fourth portion of a data message on fourth beam 210-dduring a fourth TTI, a fifth portion of a data message on fifth beam210-e during a fifth TTI, etc.

UE 115-a, for example, may configure different TCI states (e.g., adifferent configuration of antennas, ports, or antenna panels) tocommunicate via different beams 210. For instance, UE 115-a configure afirst TCI state to receive beam 210-a, a second TCI state to receivebeam 210-b, a third TCI state to receive third beam 210-c, etc. In someexamples of macro diversity, base station 105-a and UE 115-a may supportTTI (e.g., slot or mini-slot) aggregation. Each TTI of a set ofaggregated TTIs may correspond to different TCI states, to receivesignals on different beams 210.

In some examples of conventional wireless communication, macro diversitymay be limited by UE 115 TCI switching capability. UE 115-a may becapable of receiving a PDSCH on one or more beams 210, decoding thereceived PDSCH, identifying a target TCI state for a TTI, and performingthe TCI state switch. The amount of time it takes for UE 115-a toreceive and decode the PDSCH, identify the target TCI, and perform a TCIstate switch may be referred to as a TCI switching capability window. Ifone or more TCI switching points are scheduled to occur within the TCIswitching capability window, then UE 115-a may be unable to perform theone or more instances of TCI switching. Problems arising from TCIswitching within a TCI capability switching window are described ingreater detail with respect to FIGS. 3-5. TCI state configurations thatsupport macro diversity are described in greater detail with respect toFIGS. 6-10.

FIG. 3 illustrates an example of a TCI state switching scheme 300 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. In some examples, TCI state switching scheme 300 mayimplement aspects of wireless communications systems 100 and 200.

In some examples, a base station 105 may send a data signal to a UE 115.A TTI aggregation framework (e.g., slot aggregation or mini-slotaggregation) may support macro diversity. In such examples, each TTI 305of a TTI aggregation 310 may correspond to a TCI state, and each TCIstate may correspond to a different beam.

In some examples, TTI aggregation techniques may be used to allocate twoor more consecutive TTIs 305 in a single control transmission. In someexamples, the TTI aggregation technique may be a slot aggregationtechnique, a mini-slot aggregation technique, or the like.

In an illustrative example, base station 105 may schedule a datatransmission on a PDSCH. Base station 105 may transmit DCI 315-a toschedule a downlink data transmission on a number of aggregated TTIs 305of TTI aggregation 310-a. Similarly, base station 105 may transmit DCI315-b to schedule a downlink data transmission on a number of TTIs 305of TTI aggregation 310-b. In some examples, the data transmission may besent on multiple beams, which may correspond to multiple TCI states.That is, a UE may be configured to receive a downlink signal using a TCIstate (e.g., adjusting or tuning one or more antenna ports, antennapanels, or the like, to receive a beam corresponding to the TCI state).In some examples, each beam may correspond to a different TCI state. Forinstance, four different TCI states may be used to receive fourdifferent beams. In other examples, a single TCI state may correspond tomultiple beams (e.g., more refined beams). For instance, two TCI statesmay be used to receive four different beams. In some examples, differentTCI states may be configured for different TTIs. For instance, each TTI305 of a TTI aggregation 310 may correspond to a different TCI state. Inother examples, two or three consecutive TTIs may be configured toreceive downlink signals using the same TCI states. In some examples,each TTI of a TCI state period may receive downlink signals using uniqueTCI states. In some examples, a limited number of TCI states (e.g., fourTCI states) may be used repeatedly, but non-consecutively acrossmultiple TTIs (e.g., a repeating pattern of TCI states).

In some examples, base station 105 may schedule a downlink transmission.Base station 105 may send a DCI 315-a, for example, which may includescheduling information (e.g., a downlink grant). The schedulinginformation may allocate two or more consecutive TTIs 305 for thedownlink transmission. The consecutive TTIs 305 (e.g., TTI 305-a, TTI305-b, TTI 305-c, and TTI 305-d) may be referred to as a set ofaggregated TTIs 305, or a TTI aggregation (e.g., TTI aggregation 310-a).In some examples, an indication of TTI aggregation (e.g., a number ofTTIs 305 to be aggregated into a TTI aggregation 310) may be included inhigher layer signaling (e.g., RRC signaling, media access controlcontrol element (MAC CE) signaling, or the like) or a DCI 315. In someexamples, a UE 115 may receive a downlink grant including an indicationof TCI state switching points during a TTI aggregation 310. UE 115 maybe unable to perform TCI state switching during TCI switching capabilitywindow 430.

In an illustrative example, the data transmissions may be sent on fourdifferent beams. In such cases, UE 115 may be instructed to configurefour different TCI states to receive the four different beams. However,the order of TCI states that UE 115 should configure to receive the datatransmissions on the four different beams may not be the same for thedata transmission scheduled in DCI 315-a as it is for the datatransmission scheduled in DCI 315-b. That is, UE 115 may be configuredto receive a first beam on first TCI state 320 during TTI 305-a, asecond beam on second TCI state 325 during TTI 305-b, a third beam onTCI state 330 during TTI 305-c, and a fourth beam on TCI 335 during TTI305-d. UE 115 may not be scheduled during TTI 305-e, but may receive DCI315-b during TTI 305-f DCI 315-b may indicate a TTI aggregation 310-band include a downlink grant. UE 115 may be instructed to receive asecond beam on second TCI state 325 during TTI 305-f, a first beam onfirst TCI state 320 during TTI 305-g, a fourth beam on fourth TCI state335 during TTI 305-g, and a third beam on third TCI state 330 during TTI305-i.

In order to receive a scheduled data transmission, UE 115 may performTCI state switches at TTI boundaries (e.g., from first TCI state 320 tosecond TCI state 325 between TTI 305-a and TTI 305-b, etc.). However, aUE 115 may use a minimum amount of time to receive a PDSCH on one ormore beams, decode the received PDSCH, identify a target TCI state for aTTI 305, and perform the TCI state switch for the TTI 305. The amount oftime the UE 115 takes to perform these actions may be referred to as TCIswitching capability window 340. TCI switching capability window 340 maybe indicated as a number of TTIs long (e.g., two TTIs).

In some examples, UE 115 may receive an indication of a TCI stateswitching point located outside of TCI switching capability window 340(e.g., at the TTI boundary between TTI 305-c and TTI 305-d), and may becapable of performing the TCI state switch at that time. However, if theTCI state switching point indicated in DCI 315-a is located within TCIswitching capability window 340 (e.g., the TCI switching point locatedat the TTI boundary between TTI 305-a and TTI 305-b), then UE 115 may beincapable of performing TCI state switching at that TCI switching point.In an illustrative example, UE 115 may communicate in FR2 of a 5Gsystem, and granted TCI switching for a UE 115 capability may be a fewslots, which may be based on PDCCH processing time, a TCI stateconfiguration time, and the like. In some cases, TCI switching patternsfor receiving PDCCHs may be the same as TCI switching patterns forreceiving PDSCHs. In some cases, PDCCHs switching patterns may bedifferent than TCI switching patterns for receiving PDSCHs. Someapproaches to TCI state switching within TCI switching capability window340 are described in greater detail with respect to FIGS. 4 and 5. Someaspects of such approaches may be insufficient.

FIG. 4 illustrates an example of a TCI state switching scheme 400 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. In some examples, TCI state switching scheme 400 mayimplement aspects of wireless communications systems 100 and 200.

In some examples, TTI aggregation techniques may be used to allocate twoor more consecutive TTIs 405 in a single control transmission. In someexamples, the TTI aggregation technique may be a slot aggregationtechnique, a mini-slot aggregation technique, or the like.

In some examples, base station 105 may schedule a downlink transmission.Base station 105 may send a DCI 410, for example, which may includescheduling information (e.g., a downlink grant). The schedulinginformation may allocate two or more consecutive TTIs 405 for thedownlink transmission. The consecutive TTIs 405 (e.g., TTI 405-a, TTI405-b, TTI 405-c, and TTI 405-d) may be referred to as a set ofaggregated TTIs 405, or a TTI aggregation (e.g., TTI aggregation 415).In some examples, an indication of TTI aggregation (e.g., a number ofTTIs 405 to be aggregated into a TTI aggregation 415) may be included inhigher layer signaling (e.g., RRC signaling, MAC CE signaling, or thelike) or a DCI 410. In some examples, a UE 115 may receive a downlinkgrant including an indication of TCI state switching points during a TTIaggregation 415. UE 115 may be unable to perform TCI state switchingduring TCI switching capability window 430.

Base station 105 may transmit DCI 410 to UE 115. DCI 410 may include adownlink grant for a data transmission during TTI aggregation 415. TTIaggregation 415 may include a number (e.g., four) of TTIs. However, asdescribed in greater detail with respect to FIGS. 2 and 3, UE 115 may beunable to perform TCI state switching indicated by DCI 410 within TCIswitching capability window 430. That is, if DCI 410 indicated a TCIstate switch between TTI 405-a and TTI 405-b, UE 115 may be unable toperform the TCI state switch. In such examples, UE 115 may be unable toperform a TCI state switch until the TTI 405 subsequent to the last TTI405 of the TCI switching capability window 430. For instance, where theTCI switching capability window 430 is equal to two TTIs, the TCIswitching capability window 430 may begin during TTI 405-a after DCI410. TCI switching capability window 430 may end during a third TTI405-c. Because only part of TTI 405-c remains after the end of TCIswitching capability window 430, UE 115 may be unable to perform TCIstate switching until TTI 405-d.

UE 115 may perform TCI state switching after TCI switching capabilitywindow 430, which may result in decreased ability to support macrodiversity. UE 115 may receive a downlink grant in DCI 410 for a TTIaggregation 415. UE 115 may receive downlink signals on first TCI state420 during TTI 405-a, TTI 405-b, and TTI 405-b of TTI aggregation 415.First TCI state 420 may be a previously configured or previously usedTCI state, or a default TCI state. DCI 410 may also indicate that adownlink signal scheduled for TTI 405-d is to be received on second TCIstate 425. Because TTI 405-d is outside of TCI switching capabilitywindow 430, UE 115 may be capable of performing a TCI state switch fromfirst TCI state 420 to second TCI state 425 at the TTI boundary betweenTTI 405-c and TTI 405-d.

In some conventional techniques, TCI state switching may be performedonly across TTI aggregations 415. For instance, a UE may receive adownlink signal during the entirety of a TTI aggregation 415 using onlyone TCI state, and may receive another downlink signal during theentirety of another TTI aggregation. This, however, may result inincreased system latency. Switching within a TTI aggregation 415, asdescribed herein may support macro-diversity within TTI aggregations andimprove system latency. However, in a TTI aggregation 415 of four TTIs405 (where TCI switching capability window 430 is equal to two TTIs)communications with the base station 105 may be limited to two TCIstates (and two beams). This may limit macro diversity and decreasesystem efficiency and reliability. An alternative conventional approachto TCI state switching within a TCI switching capability window 430 isdescribed in greater detail with respect to FIG. 5.

FIG. 5 illustrates an example of a TCI state switching scheme 500 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. In some examples, TCI state switching scheme 500 mayimplement aspects of wireless communications systems 100 and 200.

In some examples, a UE 115 may receive a downlink grant and anindication of TCI state switching points during a TTI aggregation. UE115 may be unable to perform TCI state switching during TCI switchingcapability window 540. Instead, a downlink grant may be a cross-TTIgrant for subsequent TTIs, which may result in increased system latencyand decreased user experience. For instance, as described in greaterdetail herein, a UE 115 may receive a downlink grant in a first TTI505-a. To avoid a command to perform TCI state switching during TCIswitching capability window 540, the downlink grant may be a cross-TTIgrant for TTIs subsequent to TTI 505-c. Delaying the downlinktransmission in TTI aggregation 515 to allow TCI state switchingfollowing TCI switching capability window 540 may result in unnecessarydelays and increased system latency.

Base station 105 may send DCI 510, which may include a downlink grantduring a number of TTIs 505 (e.g., TTI 505-d, TTI 505-e, TTI 505-f, andTTI 505-g) of TTI aggregation 515. Base station 105 may schedule thedownlink transmission to be received by UE 115 on different TCI states520, 525, 530, and 535. TTIs 505 in TTI aggregation 515 may be scheduledto allow TCI state switching, for example following TCI switchingcapability window 540. The cross-TTI grant (e.g., a cross-slot grant ora cross-mini-slot) in DCI 510 may indicate TTIs 505 that are subsequentto the TTI in which DCI 510 is received. For instance, base station 105may send DCI 510 during TTI 505-a, and TCI switching capability window540 may have a duration of any number of TTIs (e.g., two TTIs). TCIswitching capability window 540 may follow DCI 510, and thus may includeall or some of three TTIs 505 (e.g., TTI 505-a, TTI 505-b, and TTI505-c. Because the UE 115 may be incapable of receiving a TCI stateconfiguration during TTI 505-a and performing TCI state switching duringany TTIs partially or totally included in TCI switching capabilitywindow 540, the downlink grant in DCI 510 may schedule the downlinktransmission during TTI aggregation 515 subsequent to the last TTI 505-cthat overlaps with TCI switching capability window 540.

Cross-TTI scheduling of downlink transmissions subsequent to the TCIswitching capability window 540 may result in a delay in transmission ofTTIs 505-a, 505-b, and 505-c, increasing system latency. In someexamples, a UE 115 may perform TCI state switching based on asemi-statically configured TCI pattern, which may decrease or avoid thesystem latency resulting from the delayed scheduling described withrespect to FIG. 5, or the decreased diversity described with respect toFIG. 4, and may increase system efficiency and improve user experience.

FIG. 6 illustrates an example of a TCI state switching scheme 600 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. In some examples, TCI state switching scheme 600 mayimplement aspects of wireless communications systems 100 and 200.

In some examples, a UE 115 may perform TCI state switching basedpartially or completely on a semi-statically configured TCI pattern. TheUE 115 may thus be able to perform TCI switching within a TCI switchingcapability window, and thereby support macro capability and avoid ordecrease system latency. A semi-statically (e.g., RRC) configuredswitching period and switching pattern may be independent from DCIdetection, and a UE 115 may perform TCI switching automatically unlessotherwise indicated by a DCI. In some examples, the RRC configuredswitching pattern may apply to control monitoring. In some examples,another RRC configured TCI pattern may indicate TCI states formonitoring for and receiving control information.

In some examples, UE 115 may receive a downlink signal (e.g., an RRCmessage), and may identify a TCI pattern based thereon. The RRCconfigured TCI pattern may include a series of TCI states. In someexamples, the RRC configured TCI pattern may include a different TCIstate for each TTI for a TCI period (e.g., a period of time before asubsequent RRC message). The RRC configured TCI pattern may also includeone or more repetitions of a sub-pattern. For example, the RRCconfigured TCI pattern may include a first TCI state 620, second TCIstate 625, third TCI state 630, and fourth TCI state 635. The four TCIstates may be repeated in the same order for the TCI period of the RRCconfigured TCI pattern. In some examples, the TCI pattern and the TCItime period may be configured via higher layer signaling (e.g., RRCsignaling, MAC CE signaling, or the like). In some cases, the RRCsignaling may also configure the UE with a TTI aggregation size (e.g.,four TTIs). UE 115 may determine the RRC configured TCI pattern, and mayreceive downlink signals in multiple TTIs according to the TCI states ofthe RRC configured TCI pattern.

In some examples, UE 115 may receive one or more downlink signals basedon the RRC configured TCI pattern. UE 115 may receive a DCI 610-a, whichmay include a downlink grant. The downlink grant may grant resources fora downlink transmission during TTI aggregation 615-a. UE 115 may tuneone or more antennas or antenna panels in accordance with the RRCconfigured TCI pattern. That is, during TTI 605-a, UE 115 may receive adownlink signal on first TCI state 620. UE 115 may perform TCI stateswitching from first TCI state 620 to second TCI state 625 at a TTIboundary to receive a second downlink signal or a second portion of thesame downlink signal on second TCI state 625 during TTI 605-b. UE 115may perform TCI state switching during TTI aggregation 615-a, includingduring TCI switching capability window 640. TCI state switching withinthe TCI switching capability window 640 may be possible because UE 115has been previously received the RRC configured TCI pattern, andtherefore does not need time for receiving, decoding, and identifyingTCI states from DCI 610-a before it can perform TCI state switching.

During non-scheduled TTIs 605-e, and 605-f, UE 115 may not receive anydownlink signals, but may subsequently be scheduled to receive a seconddownlink signal during TTI aggregation 615-b. UE 115 may receive DCI610-b, which may indicate resources during TTI aggregation 615-b forreceiving the second downlink signal. TTI aggregation 615-a may includea first TTI 605-g, which may correspond to third TCI state 630 (insteadof first TCI state 620). UE 115 may determine that the downlink signalis to be received on third TCI state 630 during TTI 605-g based on theRRC configured TCI pattern. Similarly, UE 115 may determine to receivethe downlink signal on fourth TCI state 635 during second TTI 605-h, onfirst TCI state 620 during third TTI 605-I, and on second TCI state 625during fourth TTI 605-j, based on the RRC configured TCI pattern.

In some examples, base station 105 may refrain from transmitting any TCIstate information in a DCI 610, and UE 115 may rely on the RRCconfigured TCI pattern to determine which TCI states are to be used inwhich TTIs 605. In other examples, base station 105 may include one ormore indications of a TCI state in a DCI 610. In such examples, UE 115may ignore the TCI indications in DCI 610. In some such examples, UE 115may perform TCI state switching based on TCI state indicators that applyto TTIs subsequent to TCI switching capability window 640, as describedin greater detail with respect to FIG. 7.

FIG. 7 illustrates an example of a TCI state switching scheme 700 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. In some examples, TCI state switching scheme 700 mayimplement aspects of wireless communications systems 100 and 200. Asdescribed with respect to FIG. 6, a UE 115 may receive an RRC messageindicating an RRC configured TCI pattern.

In some examples, UE 115 may perform TCI switching based on the RRCconfigured switching period and switching pattern in combination withDCI based TCI switching. UE 115 may receive a downlink grant in DCI710-a. The downlink grant may indicate resources for receiving one ormore downlink signals during one or more TTI aggregations 715. UE 115may perform TCI state switching between the various TCI states of theRRC configured TCI pattern during the TTI aggregations 715, and may notreceive any downlink signals or perform TCI state switching duringunscheduled TTIs 705 (e.g., TTI 705-e, or TTI 705-f).

In some examples, the RRC configured TCI pattern may be longer than theTCI switching capability window 740, and TCI switching outside of TCIswitching capability window 740 may be controlled partially or wholly bya DCI 710. For example, UE 115 may receive DCI 710-a during a first TTI705-a. A downlink grant in DCI 710-a may reserve resources during TTIaggregation 715-a for a downlink transmission. UE 115 may receive threedifferent beams during TTI 705-a, TTI 705-b, and TTI 705-c, by switchingto first TCI state 720, second TCI state 725, and third TCI state 730,respectively. UE 115 may perform these TCI state switches according tothe RRC configured TCI pattern during the first three TTIs 705 thatoverlap wholly or partially with the TCI switching capability window740. However, UE 115 may be capable of performing DCI configured TCIswitching for TTIs 705 outside of TCI switching capability window 740.DCI 710-a may include an indication of a fifth TCI state 745 for TTI705-d, which is the first TTI 705 located wholly outside of TCIswitching capability window 740. UE 115 may perform TCI state switchingfrom third TCI state 730 during TTI 705-c to fifth TCI state 745 duringTTI 705-d (instead of the RRC configured fourth TCI state 735 for TTI705-d) based on the TCI state indication in DCI 710-a. After performingTCI state switching based on DCI 710-a, (e.g., after expiration of atimer having a known or predetermined time duration) UE 115 may revertto performing TCI state switching based on the RRC configured TCIpattern (e.g., during TTI 795-g, TTI 7095-h, and TTI 705-i) unlessindicated by another DCI 710-b. If DCI 710-b includes another indicationof a fifth TCI state 745 for TTI 705-j, then UE 115 may similarlyperform TCI state switching based on the DCI 710-b, instead of the RRCconfigured TCI pattern during indicated TTI 705-j and may then revert toperforming TCI state switching based on the RRC configured TCI patternfor subsequent downlink transmissions.

In some examples, a DCI 710 may not specify a TCI state within the TCIswitching capability window 740 because the UE 115 may be incapable ofperforming TCI state switching based on the DCI 710 within the TCIswitching capability window 740. In such examples, base station 105 maynot specify a TCI state for TTIs 705 within TCI switching capabilitywindow 740, and UE 115 may use the default pattern (e.g., the RRCconfigured TCI pattern). In such examples, a table indicating TCI statesfor TTIs 705 of one or more TTI aggregations 715 may be smaller,resulting in extra data that can be used for other purposes.Alternatively, UE 115 may ignore entries in the table that correspond toTTIs 705 within the TCI switching capability window 740.

FIG. 8 illustrates an example of a TCI state switching scheme 800 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. In some examples, TCI state switching scheme 800 mayimplement aspects of wireless communications systems 100 and 200.

In some examples, as described in greater detail with respect to FIGS. 6and 7, UE 115 may perform TCI state switching based on an RRC configuredTCI pattern 815. In some examples, UE 115 may support Rank1communications on a single link. In some examples, UE 115 maycommunicate via more than one wireless link, and TTI aggregation may beextended to Rank2 and above.

Base station 105 may configure, via RRC signaling, the TCI pattern 815in multiple (e.g., two) dimensions. For example, the RRC configured TCIpattern 815 may include a first portion (e.g., a time domain pattern)and a second portion (e.g., a spatial domain pattern). The TCI pattern815 may include first TCI state 820, second TCI state 825, third TCIstate 830, fourth TCI state 835, fifth TCI state 840, sixth TCI state845, seventh TCI state 850, and eight TCI state 855.

In some examples, each antenna or each port of a UE 115 may follow itsown pattern. In such examples, each antenna or port (e.g., ports P0 andP1) may perform TCI state switching independently, according to its owncorresponding RRC configured TCI pattern 815. For instance, an RRCconfigured TCI pattern 815 for the first port (e.g., P0) may include aperiodic repetition of first TCI state 820, second TCI state 825, thirdTCI state 830, and fourth TCI state 835. An RRC configured TCI pattern815 for the second port (e.g., P1) may include a periodic repetition ofeight TCI state 850, sixth TCI state 845, fifth TCI state 840, andseventh TCI state 850. Dynamic port selection can be supported, suchthat one or both ports may be selected for downlink transmissions. Forinstance, an RRC message may include an indication of the TCI pattern815, and an indication of which link is required or preferred forsubsequent communications, or that both links will be utilized forsubsequent communications.

FIG. 9 illustrates an example of a TCI state switching scheme 900 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. In some examples, TCI state switching scheme 900 mayimplement aspects of wireless communications system 100.

In some examples, UE 115 may perform TCI switching based on the RRCconfigured switching period and switching pattern in combination withDCI based TCI state switching. A UE 115 may communicate with a basestation on multiple links (e.g., two links), and one link may bepreferred over the other. Additionally, base station 105 may performsingle-TTI (e.g., single-slot or single multi-slot) transmissions to UE115. UE 115 may perform TCI state switching between two TCI states forthe two links. If base station 105 is aware of which link is preferred,then base station 105 may send inactions in cross-TTI grants to changeidentified TTIs from an RRC configured TCI state to a DCI configured TCIstate.

In some examples, as described in greater detail with respect to FIGS. 6and 7, base station 105 may send an RRC message which may include anindication of an RRC configured TCI pattern. UE 115 may receive DCIs 315indicating a cross-TTI single-TTI grant. In some cases, UE 115 mayreceive single-TTI downlink transmissions in identified TTIs 905 basedon the TCI state indicated by the RRC configured TCI pattern.

In some examples, one link may be preferred over another link. Forinstance, a first link corresponding to first TCI state 920 may bepreferred over a second link corresponding to second TCI state 925. Thesecond link may fade, experience interference, or UE 115 may changelocations such that the second link is no longer successfully received.In such cases, it may be beneficial to receive transmissions using firstTCI state 920, instead of second TCI state 925.

In some examples, UE 115 may be unable to receive a DCI 910 and performTCI state switching within TCI switching capability window 940. UE 115may perform TCI switching based on an RRC configured switching patternand DCI configured TCI state switching. For instance, base station 105may send DCI 910-a, including a cross-TTI grant for a single-TTItransmission in TTI 905-f DCI 910-a may further include an indication toswitch from second TCI state 925 to first TCI state 920 for TTI 905-f UE115 may be capable of performing the indicated TCI state switch at TTI905-f, because TTI 905-f is located outside of the TCI switchingcapability window 940. UE 115 may successfully receive DCI 910-a duringTTI 905-c because the preferred beam may be received on first TCI state920. UE 115 may receive no transmission during TTI 905-d, but mayreceive a single-TTI transmission during TTI 905-e on first TCI state920, according to the RRC configured TCI pattern. UE 115 may alsoperform TCI state switching (or leave the antenna configuration alongbetween TTI 905-e and TTI 905-f) to receive the downlink transmissionscheduled by DCI 910-a during TTI 905-f on first TCI state 920. UE 115may receive a downlink transmission on first TCI state 920 during 905-gaccording to the RRC configured TCI pattern, and may receive DCI 910-b.DCI 910-b may include a downlink grant for TTI 905-h, and an indicationto perform TCI state switching from second TCI state 925 (as indicatedin the RRC configured TCI pattern) to first TCI state 920 for TTI 905-h.UE 115 may be capable of performing the indicated TCI state switch atTTI 905-h, because TTI 905-h is located outside of the TCI switchingcapability window 940 for DCI 910-b.

UE 115 may receive downlink signals in one or more of TTIs 905-g, 905-i,or 905-k, using the first TCI state 920 based on the RRC configured TCIpattern. UE 115 may also receive one or more downlink signals in one ormore of TTIs 905-j, or 905-l, using the first TCI state 920 based on anindication received in a cross-TTI grant for a single-TTI transmissionincluded in DCI 910-c, or DCI 910-d, respectively. This approach may befaster than modifying the TCI state in a future TTI (e.g., slot) thatcan be changed (e.g., via RRC signaling). UE 115 may revert to receivingdownlink signals on the TCI state of the RRC configured pattern unlessotherwise indicated by a DCI 910 (e.g., after expiration of a timerhaving a known or predetermined time duration). Subsequently, UE 115 mayreceive another RRC message with an updated RRC configured pattern thatdoes not include the non-preferred TCI state (e.g., second TCI state925).

FIG. 10 illustrates an example of a process flow 1000 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. In some examples, process flow 1000 may implement aspects ofwireless communications system 100. In some examples, process flow 1000may be implemented by UE 115-b and base station 105-b, which may beexamples of similar devices described with respect to FIGS. 1 and 2.

At 1005, base station 105-b may transmit, and UE 115-b may receive, aconfiguration message. The configuration message may be an RRC message,and may indicate a TCI state switching pattern and a TCI state switchingperiod. The indication may be explicitly or implicitly, for example byidentifying an entry in a configuration table including entries for thepatterns and periods, or by providing values also associated with otherconfiguration parameters that may be used by the UE to determine thepattern and period. The TCI state switching period may identify a numberof TTIs and the TCI state switching pattern may indicate a TCI state foreach of the TTIs in the TCI state switching period. In some examples,the RRC configuration may also indicate a TTI aggregation number, or mayinitiate a TTI aggregation mode. In other examples, the indication ofthe TTI aggregation number and/or TTI aggregation mode may be separatelyindicated, for example in separate RRC signaling.

At 1010, base station 105-b may transmit a DCI. The DCI may include adownlink grant, indicating resources for the UE 115-b to use to receivea downlink transmission from base station 105-b at 1020. In someexamples, the downlink grant may also include an indication of TCIstates for receiving a portion of the downlink signal during TTIsoutside of a known offset (e.g., outside a TCI switching capabilitywindow).

At 1015, base station 105-b may transmit a downlink signal during one ormore TTIs of the TCI switching period. The downlink signal may be a datasignal or a control signal.

At 1020, UE 115-b may perform TCI state switching. UE 115-b may receivethe downlink signal at 1015 using TCI states according to the TCI stateswitching pattern received at 1005. UE 115-b may perform TCI stateswitching solely or partly based on the TCI state switching pattern. Insome examples, UE 115 may also perform TCI state switching (on TTIsafter a known offset) based on an indication received in DCI 1010, andmay perform TCI state switching based on both the TCI state switchingpattern and the indication in the DCI. By using the RRC configured TCIstate switching pattern, the UE 115-b may support macro-diversity, anddecrease system latency.

FIG. 11 illustrates an example of a process flow 1100 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. In some examples, process flow 1100 may implement aspects ofwireless communications system 100. In some examples, process flow 1100may be implemented by UE 115-c and base station 105-c, which may beexamples of similar devices described with respect to FIGS. 1 and 2.

At 1105 base station 105-c may transmit a configuration message. Theconfiguration message may be an RRC message. In some examples, the RRCmessage may include a configuration indication a first TCI state for theUE 115-c to use for receiving downlink signals. At 1110, UE 115-c mayidentify the first TCI state based on the RRC message received at 1105.In some cases, the UE 115-c may adopt the first TCI state as a defaultTCI state.

At 1115, base station 105-c may transmit a DCI. The DCI may include adownlink grant of resources for a downlink signal to be sent at 1125 bybase station 105-c. The DCI may also include an indication of a secondTCI state. In some examples, the DCI may include a TCI state switchingindication that applies to TTIs following a known offset from the TTI inwhich the DCI is transmitted at 1115. The number TCI state entries, andthus the size of the corresponding DCI, may be decreased by excludingfrom the DCI the TCI state entries for TTIs located within the knownoffset (e.g., within a TCI switching capability window).

At 1120, UE 115-c may receive the DCI, and may identify the second TCIstate based thereon. UE 115-c may further identify one or more TTIs forwhich the second TCI state is to be used based on the DCI.

At 1125, base station 105-c may transmit a downlink signal according tothe downlink grant in the DCI. The downlink signal may be sent using TTIaggregation techniques. For instance, the downlink transmission may besent across a set of two or more aggregated TTIs.

At 1130, UE 115-c may receive a first portion of the downlink signalusing the first TCI state, according to the configuration received inthe RRC at 1105. At 1135, as indicated in the DCI at 1115, UE 115-c mayswitch from the first TCI state to the second TCI state. UE 115-c mayreceive a second portion of the downlink signal using the second TCIstate. Within the same TTI aggregation, UE 115-c may receive thedownlink signal using macro-diversity (e.g., on multiple beams), whichmay improve overall system efficiency, and decrease system latency.

FIG. 12 shows a block diagram 1200 of a device 1205 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The device 1205 may be an example of aspects of a UE 115 asdescribed herein. The device 1205 may include a receiver 1210, acommunications manager 1215, and a transmitter 1220. The device 1205 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1210 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to semi-staticTCI configuration, etc.). Information may be passed on to othercomponents of the device 1205. The receiver 1210 may be an example ofaspects of the transceiver 1520 described with reference to FIG. 15. Thereceiver 1210 may utilize a single antenna or a set of antennas.

The communications manager 1215 may receive a configuration indicating aTCI state switching pattern and a TCI state switching period, the TCIstate switching period indicating a number of a set of TTIs, and the TCIstate switching pattern indicating a TCI state for each of the set ofTTIs, perform, by the UE, TCI state switching according to the TCI stateswitching pattern and the TCI state switching period, and receive adownlink transmission during at least one of the set of TTIs of the TCIstate switching pattern. The communications manager 1215 may alsoreceive a configuration indicating a first TCI state for the UE to useto receive downlink signals, receive, in a first TTI according to thefirst TCI state indicated by the received configuration, a DCI signalindicating a second TCI state, the first TTI being one of a set of TTIsaggregated in a TTI aggregation period, switch, responsive to thereceived DCI signal, to the indicated second TCI state for a second TTIof the set of TTIs aggregated in the TTI aggregation period, and receivea downlink signal in the second TTI according to the second TCI state.The communications manager 1215 may be an example of aspects of thecommunications manager 1510 described herein.

The communications manager 1215, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 1215, or itssub-components may be executed by a general-purpose processor, a DSP, anapplication-specific integrated circuit (ASIC), a field-programmablegate array (FPGA) or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described in the presentdisclosure.

The communications manager 1215, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, thecommunications manager 1215, or its sub-components, may be a separateand distinct component in accordance with various aspects of the presentdisclosure. In some examples, the communications manager 1215, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with various aspects of the presentdisclosure.

The transmitter 1220 may transmit signals generated by other componentsof the device 1205. In some examples, the transmitter 1220 may becollocated with a receiver 1210 in a transceiver module. For example,the transmitter 1220 may be an example of aspects of the transceiver1520 described with reference to FIG. 15. The transmitter 1220 mayutilize a single antenna or a set of antennas.

In some examples, the communications manager 1215 may be implemented asan integrated circuit or chipset for a mobile device modem, and thereceiver 1210 and transmitter 1220 may be implemented as analogcomponents (e.g., amplifiers, filters, antennas) coupled with the mobiledevice modem to enable wireless transmission and reception over one ormore bands.

The communications manager 1215 as described herein may be implementedto realize one or more potential advantages. One implementation mayallow the device 1205 to receive a configuration indicating a TCI stateswitching pattern and a TCI state switching period. The TCI stateswitching pattern may indicate a TCI state for each of a plurality ofTTIs and the TCI state switching period may indicate a number of aplurality of TTIs. The TCI state switching may increase reliability andreduce latency during transmissions.

Based on techniques for implementing a TCI state switching as describedherein, a processor of a UE 115 (e.g., controlling the receiver 1210,the transmitter 1220, or the transceiver 1520 as described withreference to FIG. 15) may increase reliability and decrease signalingoverhead in the communications because the UE 115 may remain incommunication with other devices.

FIG. 13 shows a block diagram 1300 of a device 1305 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The device 1305 may be an example of aspects of a device1205, or a UE 115 as described herein. The device 1305 may include areceiver 1310, a communications manager 1315, and a transmitter 1340.The device 1305 may also include a processor. Each of these componentsmay be in communication with one another (e.g., via one or more buses).

The receiver 1310 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to semi-staticTCI configuration, etc.). Information may be passed on to othercomponents of the device 1305. The receiver 1310 may be an example ofaspects of the transceiver 1520 described with reference to FIG. 15. Thereceiver 1310 may utilize a single antenna or a set of antennas.

The communications manager 1315 may be an example of aspects of thecommunications manager 1215 as described herein. The communicationsmanager 1315 may include a configuration manager 1320, a TCI stateswitching manager 1325, a TCI state switching pattern manager 1330, anda DCI manager 1335. The communications manager 1315 may be an example ofaspects of the communications manager 1510 described herein.

The configuration manager 1320 may receive a configuration indicating aTCI state switching pattern and a TCI state switching period, the TCIstate switching period indicating a number of a set of TTIs, and the TCIstate switching pattern indicating a TCI state for each of the set ofTTIs.

The TCI state switching manager 1325 may perform, by the UE, TCI stateswitching according to the TCI state switching pattern and the TCI stateswitching period. The TCI state switching pattern manager 1330 mayreceive a downlink transmission during at least one of the set of TTIsof the TCI state switching pattern. The configuration manager 1320 mayreceive a configuration indicating a first TCI state for the UE to useto receive downlink signals.

The DCI manager 1335 may receive, in a first TTI according to the firstTCI state indicated by the received configuration, a DCI signalindicating a second TCI state, the first TTI being one of a set of TTIsaggregated in a TTI aggregation period. The TCI state switching manager1325 may switch, responsive to the received DCI signal, to the indicatedsecond TCI state for a second TTI of the set of TTIs aggregated in theTTI aggregation period and receive a downlink signal in the second TTIaccording to the second TCI state.

The transmitter 1340 may transmit signals generated by other componentsof the device 1305. In some examples, the transmitter 1340 may becollocated with a receiver 1310 in a transceiver module. For example,the transmitter 1340 may be an example of aspects of the transceiver1520 described with reference to FIG. 15. The transmitter 1340 mayutilize a single antenna or a set of antennas.

In some examples, the communications manager 1315 may be implemented asan integrated circuit or chipset for a mobile device modem, and thereceiver 1310 and transmitter 1340 may be implemented as analogcomponents (e.g., amplifiers, filters, antennas) coupled with the mobiledevice modem to enable wireless transmission and reception over one ormore bands.

The communications manager 1315 as described herein may be implementedto realize one or more potential advantages. One implementation mayallow the device 1305 to receive a configuration indicating a TCI stateswitching pattern and a TCI state switching period. The TCI stateswitching pattern may indicate a TCI state for each of a plurality ofTTIs and the TCI state switching period may indicate a number of aplurality of TTIs. The TCI state switching may increase reliability andreduce latency during transmissions.

Based on techniques for implementing a TCI state switching as describedherein, a processor of a UE 115 (e.g., controlling the receiver 1310,the transmitter 1340, or the transceiver 1520 as described withreference to FIG. 15) may increase reliability and decrease signalingoverhead in the communications because the UE 115 may remain incommunication with other devices.

FIG. 14 shows a block diagram 1400 of a communications manager 1405 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. The communications manager 1405 may be an example ofaspects of a communications manager 1215, a communications manager 1315,or a communications manager 1510 described herein. The communicationsmanager 1405 may include a configuration manager 1410, a TCI stateswitching manager 1415, a TCI state switching pattern manager 1420, aDCI manager 1425, a TTI aggregation manager 1430, a multi-link manager1435, and a control information manager 1440. Each of these modules maycommunicate, directly or indirectly, with one another (e.g., via one ormore buses).

The configuration manager 1410 may receive a configuration indicating aTCI state switching pattern and a TCI state switching period, the TCIstate switching period indicating a number of a set of TTIs, and the TCIstate switching pattern indicating a TCI state for each of the set ofTTIs.

In some examples, the configuration manager 1410 may receive aconfiguration indicating a first TCI state for the UE to use to receivedownlink signals. In some examples, the configuration manager 1410 mayreceive the configuration in RRC signaling that indicates the TCI stateswitching pattern and the TCI state switching pattern. In some examples,the configuration manager 1410 may receive the configuration in RRCsignaling that indicates the first TCI state for the UE to use toreceive downlink signals. In some cases, the configuration in the RRCsignaling further includes an indication of an aggregation mode and anindication of a number of TTIs aggregated in the TTI aggregation periodfor the aggregation mode.

The TCI state switching manager 1415 may perform, by the UE, TCI stateswitching according to the TCI state switching pattern and the TCI stateswitching period. In some examples, the TCI state switching manager 1415may switch, responsive to the received DCI signal, to the indicatedsecond TCI state for a second TTI of the set of TTIs aggregated in theTTI aggregation period. In some examples, the TCI state switchingmanager 1415 may receive a downlink signal in the second TTI accordingto the second TCI state.

In some examples, the TCI state switching manager 1415 may receive,according to a first TCI state during a first TTI of the TCI stateswitching pattern, a DCI signal that includes an indication to switch,for a second TTI of the TCI state switching pattern, to a second TCIstate different from a TCI state indicated by the TCI state switchingpattern for the second TTI. In some examples, the TCI state switchingmanager 1415 may perform TCI state switching based on the indication toswitch of the received DCI signal. In some examples, the TCI stateswitching manager 1415 may identify a first set of TCI state entries inthe TCI state table that correspond to TTIs that are located less than athreshold number of TTIs from the first TTI. In some examples, the TCIstate switching manager 1415 may switch to the indicated second TCIstate is based on the identified second set of TCI state entries.

In some examples, the TCI state switching manager 1415 may switch to theindicated second TCI state is based on the identified one or more TCIstate entries. In some examples, the TCI state switching manager 1415may perform, prior to receiving the DCI signal indicating the second TCIstate, TCI state switching according to a first TCI state switchingpattern. In some examples, the TCI state switching manager 1415 mayrevert, after the predetermined time duration, to performing TCI stateswitching according to the first TCI state switching pattern based onidentifying that a second DCI signal has not been received during thepredetermined time duration.

The TCI state switching pattern manager 1420 may receive a downlinktransmission during at least one of the set of TTIs of the TCI stateswitching pattern. In some examples, the TCI state switching patternmanager 1420 may revert, after a time duration, to performing TCI stateswitching according to the TCI state switching pattern. In some cases, anumber of different TCI states in the TCI state switching pattern isequal to a number of TTIs in the set of TTIs of the TCI state switchingperiod. In some cases, the received configuration further indicates aTCI state switching pattern and a TCI state switching period, the TCIstate switching period indicating a number of a set of TTIs, and the TCIstate switching pattern indicating a TCI state for each of the set ofTTIs, including the first TCI state for the first TTI.

The DCI manager 1425 may receive, in a first TTI according to the firstTCI state indicated by the received configuration, a DCI signalindicating a second TCI state, the first TTI being one of a set of TTIsaggregated in a TTI aggregation period. In some examples, the DCImanager 1425 may receive, according to a first TCI state during a firstTTI of the TCI state switching pattern, a DCI signal that includes agrant of resources for the downlink transmission and an indication toswitch, for a second TTI of the TCI state switching pattern, to a secondTCI state different from a TCI state indicated by the TCI stateswitching pattern for the second TTI, where. In some examples, the DCImanager 1425 may receive a DCI signal that indicates a TCI state table.In some examples, the DCI manager 1425 may identify a second set of TCIstate entries in the TCI state table that correspond to TTIs that arelocated more than the threshold number of TTIs away from the first TTI.

In some examples, the DCI manager 1425 may ignore the first set of TCIstate entries, where performing TCI state switching is based on theidentified second set of TCI state entries. In some examples, the DCImanager 1425 may receive a DCI signal that indicates a TCI state table.In some examples, the DCI manager 1425 may identify one or more TCIstate entries in the TCI state table that correspond to TTIs that aremore than a threshold number of TTIs from the first TTI, the TCI statetable lacking TCI state entries corresponding to TTIs that are less thanthe threshold number of TTIs from the first TTI, where performing TCIstate switching is based on the identified one or more TCI stateentries.

In some examples, the DCI manager 1425 may identify a first set of TCIstate entries in a TCI state table that is indicated by the received DCIsignal, the first set of TCI state entries corresponding to TTIs thatare located less than a threshold number of TTIs from the first TTI. Insome examples, the DCI manager 1425 may identify a second set of TCIstate entries in the TCI state table that correspond to TTIs that arelocated more than the threshold number of TTIs away from the first TTI.In some examples, the DCI manager 1425 may ignore the first set of TCIstate entries, where. In some examples, the DCI manager 1425 mayidentify one or more TCI state entries in a TCI state table that isindicated by the received DCI signal, the one or more TCI statescorresponding to TTIs that are more than a threshold number of TTIs fromthe first TTI, and the TCI state table lacks TCI state entriescorresponding to TTIs that are less than the threshold number of TTIsfrom the first TTI, where. In some examples, the DCI manager 1425 mayperform, for a predetermined time duration, TCI state switchingresponsive to the received DCI signal. In some cases, the downlinktransmission includes a single-TTI transmission.

The TTI aggregation manager 1430 may receive the downlink transmissionaccording to the grant of resources during at least the first TTIaccording to the first TCI state and during the second TTI according tothe second TCI state, where the downlink transmission is aggregated overat least the first TTI and the second TTI. In some cases, theconfiguration in the RRC signaling further includes an indication of anaggregation mode and an indication of a number of TTIs aggregated in aTTI aggregation period for the aggregation mode.

The multi-link manager 1435 may receive, using the first antenna portaccording to the first TCI state and using the second antenna portaccording to the second TCI state, the downlink transmission during atleast one of the set of TTIs of the TCI state switching pattern.

The control information manager 1440 may identify a second configurationindicating a second TCI state switching pattern and a second TCI stateswitching period. In some examples, receiving a downlink controlinformation signal according to the identified second configuration,where the downlink transmission received during the at least one of theset of TTIs of the TCI state switching pattern includes a downlink datatransmission.

FIG. 15 shows a diagram of a system 1500 including a device 1505 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. The device 1505 may be an example of or include thecomponents of device 1205, device 1305, or a UE 115 as described herein.The device 1505 may include components for bi-directional voice and datacommunications including components for transmitting and receivingcommunications, including a communications manager 1510, an I/Ocontroller 1515, a transceiver 1520, an antenna 1525, memory 1530, and aprocessor 1540. These components may be in electronic communication viaone or more buses (e.g., bus 1545).

The communications manager 1510 may receive a configuration indicating aTCI state switching pattern and a TCI state switching period, the TCIstate switching period indicating a number of a set of TTIs, and the TCIstate switching pattern indicating a TCI state for each of the set ofTTIs, perform, by the UE, TCI state switching according to the TCI stateswitching pattern and the TCI state switching period, and receive adownlink transmission during at least one of the set of TTIs of the TCIstate switching pattern. The communications manager 1510 may alsoreceive a configuration indicating a first TCI state for the UE to useto receive downlink signals, receive, in a first TTI according to thefirst TCI state indicated by the received configuration, a DCI signalindicating a second TCI state, the first TTI being one of a set of TTIsaggregated in a TTI aggregation period, switch, responsive to thereceived DCI signal, to the indicated second TCI state for a second TTIof the set of TTIs aggregated in the TTI aggregation period, and receivea downlink signal in the second TTI according to the second TCI state.

The I/O controller 1515 may manage input and output signals for thedevice 1505. The I/O controller 1515 may also manage peripherals notintegrated into the device 1505. In some cases, the I/O controller 1515may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 1515 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 1515may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 1515may be implemented as part of a processor. In some cases, a user mayinteract with the device 1505 via the I/O controller 1515 or viahardware components controlled by the I/O controller 1515.

The transceiver 1520 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1520 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1520 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1525.However, in some cases the device may have more than one antenna 1525,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1530 may include random-access memory (RAM) and read-onlymemory (ROM). The memory 1530 may store computer-readable,computer-executable code 1535 including instructions that, whenexecuted, cause the processor to perform various functions describedherein. In some cases, the memory 1530 may contain, among other things,a BIOS which may control basic hardware or software operation such asthe interaction with peripheral components or devices.

The processor 1540 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1540 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 1540. The processor 1540 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 1530) to cause the device 1505 to perform variousfunctions (e.g., functions or tasks supporting semi-static TCIconfiguration).

The code 1535 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1535 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1535 may not be directly executable by theprocessor 1540 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 16 shows a block diagram 1600 of a device 1605 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The device 1605 may be an example of aspects of a basestation 105 as described herein. The device 1605 may include a receiver1610, a communications manager 1615, and a transmitter 1620. The device1605 may also include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

The receiver 1610 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to semi-staticTCI configuration, etc.). Information may be passed on to othercomponents of the device 1605. The receiver 1610 may be an example ofaspects of the transceiver 1920 described with reference to FIG. 19. Thereceiver 1610 may utilize a single antenna or a set of antennas.

The communications manager 1615 may identify a TCI state switchingpattern and a TCI state switching period, the TCI state switching periodindicating a number of a set of TTIs, and the TCI state switchingpattern indicating a TCI state for each of the set of TTIs, transmit, toa UE, a configuration indicating the identified TCI state switchingpattern and the identified TCI state switching period, and transmit adownlink transmission to the UE during at least one of the set of TTIsaccording to the TCI state switching pattern and the TCI state switchingperiod. The communications manager 1615 may also transmit, to a UE, aconfiguration indicating a first TCI state for the UE to use to receivedownlink signals, transmit, in a first TTI according to the first TCIstate indicated by the transmitted configuration, a DCI signalindicating a second TCI state to which the UE is to switch, responsiveto the DCI signal, for a second TTI of a set of TTIs aggregated in a TTIaggregation period, where the first TTI is one of the set of TTIsaggregated in the TTI aggregation period, and transmit a downlink signalin the second TTI. The communications manager 1615 may be an example ofaspects of the communications manager 1910 described herein.

The communications manager 1615, or its sub-components, may beimplemented in hardware, code (e.g., software or firmware) executed by aprocessor, or any combination thereof. If implemented in code executedby a processor, the functions of the communications manager 1615, or itssub-components may be executed by a general-purpose processor, a DSP, anapplication-specific integrated circuit (ASIC), a FPGA or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described in the present disclosure.

The communications manager 1615, or its sub-components, may bephysically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations by one or more physical components. In some examples, thecommunications manager 1615, or its sub-components, may be a separateand distinct component in accordance with various aspects of the presentdisclosure. In some examples, the communications manager 1615, or itssub-components, may be combined with one or more other hardwarecomponents, including but not limited to an input/output (I/O)component, a transceiver, a network server, another computing device,one or more other components described in the present disclosure, or acombination thereof in accordance with various aspects of the presentdisclosure.

The transmitter 1620 may transmit signals generated by other componentsof the device 1605. In some examples, the transmitter 1620 may becollocated with a receiver 1610 in a transceiver module. For example,the transmitter 1620 may be an example of aspects of the transceiver1920 described with reference to FIG. 19. The transmitter 1620 mayutilize a single antenna or a set of antennas.

FIG. 17 shows a block diagram 1700 of a device 1705 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The device 1705 may be an example of aspects of a device1605, or a base station 105 as described herein. The device 1705 mayinclude a receiver 1710, a communications manager 1715, and atransmitter 1745. The device 1705 may also include a processor. Each ofthese components may be in communication with one another (e.g., via oneor more buses).

The receiver 1710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to semi-staticTCI configuration, etc.). Information may be passed on to othercomponents of the device 1705. The receiver 1710 may be an example ofaspects of the transceiver 1920 described with reference to FIG. 19. Thereceiver 1710 may utilize a single antenna or a set of antennas.

The communications manager 1715 may be an example of aspects of thecommunications manager 1615 as described herein. The communicationsmanager 1715 may include a configuration manager 1720, a TCI stateswitching pattern manager 1725, a TCI state switching manager 1730, aDCI manager 1735, and a TTI aggregation manager 1740. The communicationsmanager 1715 may be an example of aspects of the communications manager1910 described herein.

The configuration manager 1720 may identify a TCI state switchingpattern and a TCI state switching period, the TCI state switching periodindicating a number of a set of TTIs, and the TCI state switchingpattern indicating a TCI state for each of the set of TTIs and transmit,to a UE, a configuration indicating the identified TCI state switchingpattern and the identified TCI state switching period.

The TCI state switching pattern manager 1725 may transmit a downlinktransmission to the UE during at least one of the set of TTIs accordingto the TCI state switching pattern and the TCI state switching period.The TCI state switching manager 1730 may transmit, to a UE, aconfiguration indicating a first TCI state for the UE to use to receivedownlink signals.

The DCI manager 1735 may transmit, in a first TTI according to the firstTCI state indicated by the transmitted configuration, a DCI signalindicating a second TCI state to which the UE is to switch, responsiveto the DCI signal, for a second TTI of a set of TTIs aggregated in a TTIaggregation period, where the first TTI is one of the set of TTIsaggregated in the TTI aggregation period. The TTI aggregation manager1740 may transmit a downlink signal in the second TTI.

The transmitter 1745 may transmit signals generated by other componentsof the device 1705. In some examples, the transmitter 1745 may becollocated with a receiver 1710 in a transceiver module. For example,the transmitter 1745 may be an example of aspects of the transceiver1920 described with reference to FIG. 19. The transmitter 1745 mayutilize a single antenna or a set of antennas.

FIG. 18 shows a block diagram 1800 of a communications manager 1805 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. The communications manager 1805 may be an example ofaspects of a communications manager 1615, a communications manager 1715,or a communications manager 1910 described herein. The communicationsmanager 1805 may include a configuration manager 1810, a TCI stateswitching pattern manager 1815, a DCI manager 1820, a TTI aggregationmanager 1825, a multi-link manager 1830, and a TCI state switchingmanager 1835. Each of these modules may communicate, directly orindirectly, with one another (e.g., via one or more buses).

The configuration manager 1810 may identify a TCI state switchingpattern and a TCI state switching period, the TCI state switching periodindicating a number of a set of TTIs, and the TCI state switchingpattern indicating a TCI state for each of the set of TTIs. In someexamples, the configuration manager 1810 may transmit, to a UE, aconfiguration indicating the identified TCI state switching pattern andthe identified TCI state switching period. In some examples, theconfiguration manager 1810 may transmit the configuration in RRCsignaling that indicates the TCI state switching pattern and the TCIstate switching pattern.

In some examples, the configuration manager 1810 may transmit theconfiguration in RRC signaling that indicates the first TCI state forthe UE to use to receive downlink signals. In some cases, the downlinktransmission includes a single-TTI transmission. In some cases, theconfiguration in the RRC signaling further includes an indication of anaggregation mode and an indication of a number of TTIs aggregated in aTTI aggregation period for the aggregation mode. In some cases, thetransmitted configuration further indicates a TCI state switchingpattern and a TCI state switching period, the TCI state switching periodindicating a number of a set of TTIs, and the TCI state switchingpattern indicating a TCI state for each of the set of TTIs, includingthe first TCI state for the first TTI. In some cases, the configurationin the RRC signaling further includes an indication of an aggregationmode and an indication of a number of TTIs aggregated in the TTIaggregation period for the aggregation mode.

The TCI state switching pattern manager 1815 may transmit a downlinktransmission to the UE during at least one of the set of TTIs accordingto the TCI state switching pattern and the TCI state switching period.In some cases, a number of different TCI states in the TCI stateswitching pattern is equal to a number of TTIs in the set of TTIs of theTCI state switching period.

The DCI manager 1820 may transmit, in a first TTI according to the firstTCI state indicated by the transmitted configuration, a DCI signalindicating a second TCI state to which the UE is to switch, responsiveto the DCI signal, for a second TTI of a set of TTIs aggregated in a TTIaggregation period, where the first TTI is one of the set of TTIsaggregated in the TTI aggregation period.

In some examples, the DCI manager 1820 may transmit, according to afirst TCI state during a first TTI of the TCI state switching pattern, aDCI signal that includes a grant of resources for the downlinktransmission and an indication for the UE to switch, for a second TTI ofthe TCI state switching pattern, to a second TCI state different from aTCI state indicated by the TCI state switching pattern for the secondTTI, where. In some examples, transmitting, to the UE, a downlinkcontrol information signal according to the identified secondconfiguration, where the downlink transmission transmitted to the UEduring the at least one of the set of TTIs according to the TCI stateswitching pattern and the TCI state switching period includes a downlinkdata transmission.

In some examples, the DCI manager 1820 may transmit, according to afirst TCI state during a first TTI of the TCI state switching pattern, aDCI signal that includes an indication for the UE to switch, for asecond TTI of the TCI state switching pattern, to a second TCI statedifferent from a TCI state indicated by the TCI state switching patternfor the second TTI, and for the UE to revert, after a time duration, toperforming TCI state switching according to the TCI state switchingpattern. In some examples, the DCI manager 1820 may transmit a DCIsignal that indicates a TCI state table, the TCI including a first setof TCI state entries that correspond to TTIs that are located less thana threshold number of TTIs from the first TTI, and including a secondset of TCI state entries that correspond to TTIs that are located morethan the threshold number of TTIs away from the first TTI, the UE toignore the first set of TCI state entries when performing TCI stateswitching based on the identified second set of TCI state entries.

In some examples, the DCI manager 1820 may transmit a DCI signal thatindicates a TCI state table, one or more TCI state entries in the TCIstate table corresponding to TTIs that are more than a threshold numberof TTIs from the first TTI, and the TCI state table lacking TCI stateentries corresponding to TTIs that are less than the threshold number ofTTIs from the first TTI. In some examples, the DCI manager 1820 mayidentify a first set of TCI state entries for a TCI state table, thefirst set of TCI state entries corresponding to TTIs that are locatedless than a threshold number of TTIs from the first TTI. In someexamples, the DCI manager 1820 may identify a second set of TCI stateentries for the TCI state table that correspond to TTIs that are locatedmore than the threshold number of TTIs away from the first TTI.

In some examples, the DCI manager 1820 may transmit, to the UE, anindication of the TCI state table in the DCI signal, the UE to ignorethe first set of TCI state entries when switching to the indicatedsecond TCI state based on the second set of TCI state entries. In someexamples, the DCI manager 1820 may transmit, to the UE, an indication ofthe TCI state table in the DCI signal.

The TTI aggregation manager 1825 may transmit a downlink signal in thesecond TTI. In some examples, the TTI aggregation manager 1825 maytransmit the downlink transmission according to the grant of resourcesduring at least the first TTI according to the first TCI state andduring the second TTI according to the second TCI state, where thedownlink transmission is aggregated over at least the first TTI and thesecond TTI.

The TCI state switching manager 1835 may transmit, to a UE, aconfiguration indicating a first TCI state for the UE to use to receivedownlink signals. In some examples, the TCI state switching manager 1835may identify a second configuration indicating a second TCI stateswitching pattern and a second TCI state switching period. In someexamples, the TCI state switching manager 1835 may transmit, to the UE,an indication of the second configuration. In some examples, the TCIstate switching manager 1835 may identify one or more TCI state entriesfor a TCI state table, the one or more TCI states corresponding to TTIsthat are more than a threshold number of TTIs from the first TTI, theTCI state table lacking TCI state entries corresponding to TTIs that areless than the threshold number of TTIs from the first TTI. In someexamples, the TCI state switching manager 1835 may transmit anindication for the UE to revert, after a predetermined time duration, toperforming TCI state switching according to a first TCI state switchingpattern based on identifying that a second DCI signal has not beenreceived during the predetermined time duration.

The multi-link manager 1830 may configure a TCI state switching patternthat includes a first TCI state associated with a first antenna port foreach of the plurality of TTIs and a second TCI state associated with asecond antenna port for each of the plurality of TTIs, so that the UEmay receive the downlink transmission using the first antenna portaccording to the first TCI state and using the second antenna portaccording to the second TCI state, the downlink transmission during atleast one of the plurality of TTIs of the TCI state switching pattern.In some cases, the TCI state switching pattern includes a first TCIstate associated with a first antenna port for each of the set of TTIsand a second TCI state associated with a second antenna port for each ofthe set of TTIs, the UE to receive the downlink transmission using thefirst antenna port according to the first TCI state and using the secondantenna port according to the second TCI state, the downlinktransmission during at least one of the set of TTIs of the TCI stateswitching pattern.

FIG. 19 shows a diagram of a system 1900 including a device 1905 thatsupports semi-static TCI configuration in accordance with aspects of thepresent disclosure. The device 1905 may be an example of or include thecomponents of device 1605, device 1705, or a base station 105 asdescribed herein. The device 1905 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including a communicationsmanager 1910, a network communications manager 1915, a transceiver 1920,an antenna 1925, memory 1930, a processor 1940, and an inter-stationcommunications manager 1945. These components may be in electroniccommunication via one or more buses (e.g., bus 1950).

The communications manager 1910 may identify a TCI state switchingpattern and a TCI state switching period, the TCI state switching periodindicating a number of a set of TTIs, and the TCI state switchingpattern indicating a TCI state for each of the set of TTIs, transmit, toa UE, a configuration indicating the identified TCI state switchingpattern and the identified TCI state switching period, and transmit adownlink transmission to the UE during at least one of the set of TTIsaccording to the TCI state switching pattern and the TCI state switchingperiod. The communications manager 1910 may also transmit, to a UE, aconfiguration indicating a first TCI state for the UE to use to receivedownlink signals, transmit, in a first TTI according to the first TCIstate indicated by the transmitted configuration, a DCI signalindicating a second TCI state to which the UE is to switch, responsiveto the DCI signal, for a second TTI of a set of TTIs aggregated in a TTIaggregation period, where the first TTI is one of the set of TTIsaggregated in the TTI aggregation period, and transmit a downlink signalin the second TTI.

The network communications manager 1915 may manage communications withthe core network (e.g., via one or more wired backhaul links). Forexample, the network communications manager 1915 may manage the transferof data communications for client devices, such as one or more UEs 115.

The transceiver 1920 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1920 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1920 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1925.However, in some cases the device may have more than one antenna 1925,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1930 may include RAM, ROM, or a combination thereof. Thememory 1930 may store computer-readable code 1935 including instructionsthat, when executed by a processor (e.g., the processor 1940) cause thedevice to perform various functions described herein. In some cases, thememory 1930 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1940 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1940 may be configured to operate a memoryarray using a memory controller. In some cases, a memory controller maybe integrated into processor 1940. The processor 1940 may be configuredto execute computer-readable instructions stored in a memory (e.g., thememory 1930) to cause the device 1905 to perform various functions(e.g., functions or tasks supporting semi-static TCI configuration).

The inter-station communications manager 1945 may manage communicationswith other base station 105, and may include a controller or schedulerfor controlling communications with UEs 115 in cooperation with otherbase stations 105. For example, the inter-station communications manager1945 may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, the inter-station communications manager1945 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

The code 1935 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1935 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1935 may not be directly executable by theprocessor 1940 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 20 shows a flowchart illustrating a method 2000 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The operations of method 2000 may be implemented by a UE 115or its components as described herein. For example, the operations ofmethod 2000 may be performed by a communications manager as describedwith reference to FIGS. 12 through 15. In some examples, a UE mayexecute a set of instructions to control the functional elements of theUE to perform the functions described herein. Additionally oralternatively, a UE may perform aspects of the functions describedherein using special-purpose hardware.

At 2005, the UE may receive a configuration indicating a TCI stateswitching pattern and a TCI state switching period, the TCI stateswitching period indicating a number of a set of TTIs, and the TCI stateswitching pattern indicating a TCI state for each of the set of TTIs.The operations of 2005 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2005may be performed by a configuration manager as described with referenceto FIGS. 12 through 15.

At 2010, the UE may perform, by the UE, TCI state switching according tothe TCI state switching pattern and the TCI state switching period. Theoperations of 2010 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2010 may beperformed by a TCI state switching manager as described with referenceto FIGS. 12 through 15.

At 2015, the UE may receive a downlink transmission during at least oneof the set of TTIs of the TCI state switching pattern. The operations of2015 may be performed according to the methods described herein. In someexamples, aspects of the operations of 2015 may be performed by a TCIstate switching pattern manager as described with reference to FIGS. 12through 15.

FIG. 21 shows a flowchart illustrating a method 2100 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The operations of method 2100 may be implemented by a UE 115or its components as described herein. For example, the operations ofmethod 2100 may be performed by a communications manager as describedwith reference to FIGS. 12 through 15. In some examples, a UE mayexecute a set of instructions to control the functional elements of theUE to perform the functions described herein. Additionally oralternatively, a UE may perform aspects of the functions describedherein using special-purpose hardware.

At 2105, the UE may receive a configuration indicating a TCI stateswitching pattern and a TCI state switching period, the TCI stateswitching period indicating a number of a set of TTIs, and the TCI stateswitching pattern indicating a TCI state for each of the set of TTIs.The operations of 2105 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2105may be performed by a configuration manager as described with referenceto FIGS. 12 through 15.

At 2110, the UE may receive, according to a first TCI state during afirst TTI of the TCI state switching pattern, a DCI signal that includesa grant of resources for the downlink transmission and an indication toswitch, for a second TTI of the TCI state switching pattern, to a secondTCI state different from a TCI state indicated by the TCI stateswitching pattern for the second TTI, where. The operations of 2110 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 2110 may be performed by a DCImanager as described with reference to FIGS. 12 through 15.

At 2115, the UE may perform, by the UE, TCI state switching according tothe TCI state switching pattern and the TCI state switching period. Theoperations of 2115 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2115 may beperformed by a TCI state switching manager as described with referenceto FIGS. 12 through 15.

At 2120, the UE may receive a downlink transmission during at least oneof the set of TTIs of the TCI state switching pattern. The operations of2120 may be performed according to the methods described herein andaccording to the grant of resources during at least the first TTIaccording to the first TCI state and during the second TTI according tothe second TCI state, where the downlink transmission is aggregated overat least the first TTI and the second TTI. In some examples, aspects ofthe operations of 2120 may be performed by a TCI state switching patternmanager as described with reference to FIGS. 12 through 15.

FIG. 22 shows a flowchart illustrating a method 2200 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The operations of method 2200 may be implemented by a UE 115or its components as described herein. For example, the operations ofmethod 2200 may be performed by a communications manager as describedwith reference to FIGS. 12 through 15. In some examples, a UE mayexecute a set of instructions to control the functional elements of theUE to perform the functions described herein. Additionally oralternatively, a UE may perform aspects of the functions describedherein using special-purpose hardware.

At 2205, the UE may receive a configuration indicating a TCI stateswitching pattern and a TCI state switching period, the TCI stateswitching period indicating a number of a set of TTIs, and the TCI stateswitching pattern indicating a TCI state for each of the set of TTIs.The operations of 2205 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2205may be performed by a configuration manager as described with referenceto FIGS. 12 through 15.

At 2210, the UE may receive, according to a first TCI state during afirst TTI of the TCI state switching pattern, a DCI signal that includesa grant of resources for the downlink transmission and an indication toswitch, for a second TTI of the TCI state switching pattern, to a secondTCI state different from a TCI state indicated by the TCI stateswitching pattern for the second TTI, where. The operations of 2210 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 2210 may be performed by a DCImanager as described with reference to FIGS. 12 through 15.

At 2215, the UE may perform, by the UE, TCI state switching according tothe TCI state switching pattern and the TCI state switching period. Theoperations of 2215 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2215 may beperformed by a TCI state switching manager as described with referenceto FIGS. 12 through 15.

At 2220, the UE may receive a downlink transmission including asingle-TTI transmission during at least one of the set of TTIs of theTCI state switching pattern. The operations of 2220 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2220 may be performed by a TCI state switching patternmanager as described with reference to FIGS. 12 through 15.

FIG. 23 shows a flowchart illustrating a method 2300 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The operations of method 2300 may be implemented by a UE 115or its components as described herein. For example, the operations ofmethod 2300 may be performed by a communications manager as describedwith reference to FIGS. 12 through 15. In some examples, a UE mayexecute a set of instructions to control the functional elements of theUE to perform the functions described herein. Additionally oralternatively, a UE may perform aspects of the functions describedherein using special-purpose hardware.

At 2305, the UE may receive a configuration indicating a first TCI statefor the UE to use to receive downlink signals. The operations of 2305may be performed according to the methods described herein. In someexamples, aspects of the operations of 2305 may be performed by aconfiguration manager as described with reference to FIGS. 12 through15.

At 2310, the UE may receive, in a first TTI according to the first TCIstate indicated by the received configuration, a DCI signal indicating asecond TCI state, the first TTI being one of a set of TTIs aggregated ina TTI aggregation period. The operations of 2310 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2310 may be performed by a DCI manager as describedwith reference to FIGS. 12 through 15.

At 2315, the UE may switch, responsive to the received DCI signal, tothe indicated second TCI state for a second TTI of the set of TTIsaggregated in the TTI aggregation period. The operations of 2315 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2315 may be performed by a TCI stateswitching manager as described with reference to FIGS. 12 through 15.

At 2320, the UE may receive a downlink signal in the second TTIaccording to the second TCI state. The operations of 2320 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2320 may be performed by a TCI stateswitching manager as described with reference to FIGS. 12 through 15.

FIG. 24 shows a flowchart illustrating a method 2400 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The operations of method 2400 may be implemented by a basestation 105 or its components as described herein. For example, theoperations of method 2400 may be performed by a communications manageras described with reference to FIGS. 16 through 19. In some examples, abase station may execute a set of instructions to control the functionalelements of the base station to perform the functions described herein.Additionally or alternatively, a base station may perform aspects of thefunctions described herein using special-purpose hardware.

At 2405, the base station may identify a TCI state switching pattern anda TCI state switching period, the TCI state switching period indicatinga number of a set of TTIs, and the TCI state switching patternindicating a TCI state for each of the set of TTIs. The operations of2405 may be performed according to the methods described herein. In someexamples, aspects of the operations of 2405 may be performed by aconfiguration manager as described with reference to FIGS. 16 through19.

At 2410, the base station may transmit, to a UE, a configurationindicating the identified TCI state switching pattern and the identifiedTCI state switching period. The operations of 2410 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2410 may be performed by a configuration manager asdescribed with reference to FIGS. 16 through 19.

At 2415, the base station may transmit a downlink transmission to the UEduring at least one of the set of TTIs according to the TCI stateswitching pattern and the TCI state switching period. The operations of2415 may be performed according to the methods described herein. In someexamples, aspects of the operations of 2415 may be performed by a TCIstate switching pattern manager as described with reference to FIGS. 16through 19.

FIG. 25 shows a flowchart illustrating a method 2500 that supportssemi-static TCI configuration in accordance with aspects of the presentdisclosure. The operations of method 2500 may be implemented by a basestation 105 or its components as described herein. For example, theoperations of method 2500 may be performed by a communications manageras described with reference to FIGS. 16 through 19. In some examples, abase station may execute a set of instructions to control the functionalelements of the base station to perform the functions described herein.Additionally or alternatively, a base station may perform aspects of thefunctions described herein using special-purpose hardware.

At 2505, the base station may transmit, to a UE, a configurationindicating a first TCI state for the UE to use to receive downlinksignals. The operations of 2505 may be performed according to themethods described herein. In some examples, aspects of the operations of2505 may be performed by a TCI state switching manager as described withreference to FIGS. 16 through 19.

At 2510, the base station may transmit, in a first TTI according to thefirst TCI state indicated by the transmitted configuration, a DCI signalindicating a second TCI state to which the UE is to switch, responsiveto the DCI signal, for a second TTI of a set of TTIs aggregated in a TTIaggregation period, where the first TTI is one of the set of TTIsaggregated in the TTI aggregation period. The operations of 2510 may beperformed according to the methods described herein. In some examples,aspects of the operations of 2510 may be performed by a DCI manager asdescribed with reference to FIGS. 16 through 19.

At 2515, the base station may transmit a downlink signal in the secondTTI. The operations of 2515 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2515may be performed by a TTI aggregation manager as described withreference to FIGS. 16 through 19.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), OFDMA, single carrier frequency division multiple access(SC-FDMA), and other systems. A CDMA system may implement a radiotechnology such as CDMA2000, Universal Terrestrial Radio Access (UTRA),etc. CDMA2000 covers IS-2000, IS-95, and IS-856 standards. IS-2000Releases may be commonly referred to as CDMA2000 1×, 1×, etc. IS-856(TIA-856) is commonly referred to as CDMA2000 1×EV-DO, High Rate PacketData (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variantsof CDMA. A TDMA system may implement a radio technology such as GlobalSystem for Mobile Communications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned herein as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEs115 with service subscriptions with the network provider. A small cellmay be associated with a lower-powered base station 105, as comparedwith a macro cell, and a small cell may operate in the same or different(e.g., licensed, unlicensed, etc.) frequency bands as macro cells. Smallcells may include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs 115 with servicesubscriptions with the network provider. A femto cell may also cover asmall geographic area (e.g., a home) and may provide restricted accessby UEs 115 having an association with the femto cell (e.g., UEs 115 in aclosed subscriber group (CSG), UEs 115 for users in the home, and thelike). An eNB for a macro cell may be referred to as a macro eNB. An eNBfor a small cell may be referred to as a small cell eNB, a pico eNB, afemto eNB, or a home eNB. An eNB may support one or multiple (e.g., two,three, four, and the like) cells, and may also support communicationsusing one or multiple component carriers.

The wireless communications system 100 or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations 105 may have similar frame timing, andtransmissions from different base stations 105 may be approximatelyaligned in time. For asynchronous operation, the base stations 105 mayhave different frame timing, and transmissions from different basestations 105 may not be aligned in time. The techniques described hereinmay be used for either synchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), anapplication-specific integrated circuit (ASIC), a FPGA or otherprogrammable logic device (PLD), discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described herein. A general-purpose processor maybe a microprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices(e.g., a combination of a DSP and a microprocessor, multiplemicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable read only memory(EEPROM), flash memory, compact disk (CD) ROM or other optical diskstorage, magnetic disk storage or other magnetic storage devices, or anyother non-transitory medium that can be used to carry or store desiredprogram code means in the form of instructions or data structures andthat can be accessed by a general-purpose or special-purpose computer,or a general-purpose or special-purpose processor. Also, any connectionis properly termed a computer-readable medium. For example, if thesoftware is transmitted from a website, server, or other remote sourceusing a coaxial cable, fiber optic cable, twisted pair, digitalsubscriber line (DSL), or wireless technologies such as infrared, radio,and microwave, then the coaxial cable, fiber optic cable, twisted pair,DSL, or wireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communication at a userequipment (UE), comprising: receiving a configuration message indicatinga transmission configuration indicator (TCI) state switching pattern anda TCI state switching period, the TCI state switching period indicatinga number of a plurality of transmission time intervals (TTIs), and theTCI state switching pattern indicating a TCI state for each of theplurality of TTIs; performing TCI state switching according to the TCIstate switching pattern and the TCI state switching period indicated inthe configuration message; and receiving a downlink transmission duringat least one of the plurality of TTIs of the TCI state switchingpattern.
 2. The method of claim 1, further comprising: receiving,according to a first TCI state during a first TTI of the TCI stateswitching pattern, a downlink control information (DCI) signal thatincludes a grant of resources for the downlink transmission and anindication to switch, for a second TTI of the TCI state switchingpattern, to a second TCI state different from a TCI state indicated bythe TCI state switching pattern for the second TTI, wherein receivingthe downlink transmission comprises: receiving the downlink transmissionaccording to the grant of resources at least during the second TTIaccording to the second TCI state.
 3. The method of claim 2, whereinreceiving the downlink transmission comprises: receiving the downlinktransmission according to the grant of resources during at least thefirst TTI according to the first TCI state and during the second TTIaccording to the second TCI state, wherein the downlink transmission isaggregated over at least the first TTI and the second TTI.
 4. The methodof claim 2, wherein the downlink transmission comprises a single-TTItransmission.
 5. The method of claim 1, wherein the TCI state switchingpattern comprises a first TCI state associated with a first antenna portfor each of the plurality of TTIs and a second TCI state associated witha second antenna port for each of the plurality of TTIs, and whereinreceiving the downlink transmission comprises: receiving, using thefirst antenna port according to the first TCI state and using the secondantenna port according to the second TCI state, the downlinktransmission during at least one of the plurality of TTIs of the TCIstate switching pattern.
 6. The method of claim 1, further comprising:identifying a second configuration message indicating a second TCI stateswitching pattern and a second TCI state switching period; and receivinga downlink control information signal according to the identified secondconfiguration message, wherein the downlink transmission received duringthe at least one of the plurality of TTIs of the TCI state switchingpattern comprises a downlink data transmission.
 7. The method of claim1, wherein receiving the configuration message comprises: receiving theconfiguration message in radio resource control (RRC) signaling thatindicates the TCI state switching pattern and the TCI state switchingperiod.
 8. The method of claim 7, wherein the configuration message inthe RRC signaling further comprises an indication of an aggregation modeand an indication of a number of TTIs aggregated in a TTI aggregationperiod for the aggregation mode.
 9. The method of claim 1, furthercomprising: receiving, according to a first TCI state during a first TTIof the TCI state switching pattern, a downlink control information (DCI)signal that includes an indication to switch, for a second TTI of theTCI state switching pattern, to a second TCI state different from a TCIstate indicated by the TCI state switching pattern for the second TTI;performing TCI state switching based at least in part on the indicationto switch of the received DCI signal; and reverting, after a timeduration, to performing TCI state switching according to the TCI stateswitching pattern.
 10. The method of claim 1, further comprising:receiving a downlink control information (DCI) signal that indicates aTCI state table; identifying a first set of TCI state entries in the TCIstate table that correspond to TTIs that are located less than athreshold number of TTIs from the first TTI; identifying a second set ofTCI state entries in the TCI state table that correspond to TTIs thatare located more than the threshold number of TTIs away from the firstTTI; and ignoring the first set of TCI state entries, wherein performingTCI state switching is based at least in part on the identified secondset of TCI state entries.
 11. The method of claim 1, further comprising:receiving a downlink control information (DCI) signal that indicates aTCI state table; and identify one or more TCI state entries in the TCIstate table that correspond to TTIs that are more than a thresholdnumber of TTIs from the first TTI, the TCI state table lacking TCI stateentries corresponding to TTIs that are less than the threshold number ofTTIs from the first TTI, wherein performing TCI state switching is basedat least in part on the identified one or more TCI state entries. 12.The method of claim 1, wherein a number of different TCI states in theTCI state switching pattern is equal to a number of TTIs in theplurality of TTIs of the TCI state switching period.
 13. The method ofclaim 1, further comprising: receiving, in a first TTI according to afirst TCI state indicated by the received configuration message, adownlink control information (DCI) signal indicating a second TCI state,the first TTI being one of a plurality of TTIs aggregated in a TTIaggregation period; switching, responsive to the received DCI signal, tothe indicated second TCI state for a second TTI of the plurality of TTIsaggregated in the TTI aggregation period; and receiving a downlinksignal in the second TTI according to the second TCI state.
 14. Themethod of claim 13, further comprising: identifying a first set of TCIstate entries in a TCI state table that is indicated by the received DCIsignal, the first set of TCI state entries corresponding to TTIs thatare located less than a threshold number of TTIs from the first TTI;identifying a second set of TCI state entries in the TCI state tablethat correspond to TTIs that are located more than the threshold numberof TTIs away from the first TTI; ignoring the first set of TCI stateentries; and switching to the indicated second TCI state is based atleast in part on the identified second set of TCI state entries.
 15. Themethod of claim 13, further comprising: identifying one or more TCIstate entries in a TCI state table that is indicated by the received DCIsignal, one or more TCI states corresponding to TTIs that are more thana threshold number of TTIs from the first TTI, and the TCI state tablelacks TCI state entries corresponding to TTIs that are less than thethreshold number of TTIs from the first TTI; and switching to theindicated second TCI state is based at least in part on the identifiedone or more TCI state entries.
 16. The method of claim 13, furthercomprising: performing, prior to receiving the DCI signal indicating thesecond TCI state, TCI state switching according to a first TCI stateswitching pattern; performing, for a predetermined time duration, TCIstate switching responsive to the received DCI signal; and reverting,after the predetermined time duration, to performing TCI state switchingaccording to the first TCI state switching pattern based at least inpart on identifying that a second DCI signal has not been receivedduring the predetermined time duration.
 17. A method for wirelesscommunication at a base station, comprising: identifying a transmissionconfiguration indicator (TCI) state switching pattern and a TCI stateswitching period, the TCI state switching period indicating a number ofa plurality of transmission time intervals (TTIs), and the TCI stateswitching pattern indicating a TCI state for each of the plurality ofTTIs; transmitting, to a user equipment (UE), a configuration messageindicating the identified TCI state switching pattern and the identifiedTCI state switching period; and transmitting a downlink transmission tothe UE during at least one of the plurality of TTIs according to the TCIstate switching pattern and the TCI state switching period indicated inthe configuration message.
 18. The method of claim 17, furthercomprising: transmitting, according to a first TCI state during a firstTTI of the TCI state switching pattern, a downlink control information(DCI) signal that includes a grant of resources for the downlinktransmission and an indication for the UE to switch, for a second TTI ofthe TCI state switching pattern, to a second TCI state different from aTCI state indicated by the TCI state switching pattern for the secondTTI; and transmitting the downlink transmission comprises transmittingthe downlink transmission according to the grant of resources at leastduring the second TTI according to the second TCI state.
 19. The methodof claim 18, wherein transmitting the downlink transmission comprises:transmitting the downlink transmission according to the grant ofresources during at least the first TTI according to the first TCI stateand during the second TTI according to the second TCI state, wherein thedownlink transmission is aggregated over at least the first TTI and thesecond TTI.
 20. The method of claim 17, further comprising: identifyinga second configuration message indicating a second TCI state switchingpattern and a second TCI state switching period; transmitting, to theUE, an indication of the second configuration message; and transmitting,to the UE, a downlink control information signal according to theidentified second configuration message, wherein the downlinktransmission transmitted to the UE during the at least one of theplurality of TTIs according to the TCI state switching pattern and theTCI state switching period comprises a downlink data transmission. 21.The method of claim 17, wherein transmitting the configuration messagecomprises: transmitting the configuration message in radio resourcecontrol (RRC) signaling that indicates the TCI state switching patternand the TCI state switching period.
 22. The method of claim 17, furthercomprising: transmitting, according to a first TCI state during a firstTTI of the TCI state switching pattern, a downlink control information(DCI) signal that includes an indication for the UE to switch, for asecond TTI of the TCI state switching pattern, to a second TCI statedifferent from a TCI state indicated by the TCI state switching patternfor the second TTI, and for the UE to revert, after a time duration, toperforming TCI state switching according to the TCI state switchingpattern.
 23. The method of claim 17, further comprising: transmitting adownlink control information (DCI) signal that indicates a TCI statetable, the TCI state table including a first set of TCI state entriesthat correspond to TTIs that are located less than a threshold number ofTTIs from the first TTI, and including a second set of TCI state entriesthat correspond to TTIs that are located more than the threshold numberof TTIs away from the first TTI, the UE to ignore the first set of TCIstate entries when performing TCI state switching based at least in parton the identified second set of TCI state entries.
 24. The method ofclaim 17, further comprising: transmitting a downlink controlinformation (DCI) signal that indicates a TCI state table, one or moreTCI state entries in the TCI state table corresponding to TTIs that aremore than a threshold number of TTIs from the first TTI, and the TCIstate table lacking TCI state entries corresponding to TTIs that areless than the threshold number of TTIs from the first TTI.
 25. Themethod of claim 17, comprising: transmitting, in a first TTI accordingto a first TCI state indicated by the transmitted configuration message,a downlink control information (DCI) signal indicating a second TCIstate to which the UE is to switch, responsive to the DCI signal, for asecond TTI of a plurality of TTIs aggregated in a TTI aggregationperiod, wherein the first TTI is one of the plurality of TTIs aggregatedin the TTI aggregation period; and transmitting a downlink signal in thesecond TTI.
 26. The method of claim 25, further comprising: identifyinga first set of TCI state entries for a TCI state table, the first set ofTCI state entries corresponding to TTIs that are located less than athreshold number of TTIs from the first TTI; identifying a second set ofTCI state entries for the TCI state table that correspond to TTIs thatare located more than the threshold number of TTIs away from the firstTTI; and transmitting, to the UE, an indication of the TCI state tablein the DCI signal, the UE to ignore the first set of TCI state entrieswhen switching to the indicated second TCI state based at least in parton the second set of TCI state entries.
 27. The method of claim 25,further comprising: identifying one or more TCI state entries for a TCIstate table, one or more TCI states corresponding to TTIs that are morethan a threshold number of TTIs from the first TTI, the TCI state tablelacking TCI state entries corresponding to TTIs that are less than thethreshold number of TTIs from the first TTI; and transmitting, to theUE, an indication of the TCI state table in the DCI signal.
 28. Anapparatus for wireless communication at a user equipment (UE),comprising: a processor; memory in electronic communication with theprocessor; and instructions stored in the memory and executable by theprocessor to cause the apparatus to: receive a configuration messageindicating a transmission configuration indicator (TCI) state switchingpattern and a TCI state switching period, the TCI state switching periodindicating a number of a plurality of transmission time intervals(TTIs), and the TCI state switching pattern indicating a TCI state foreach of the plurality of TTIs; perform TCI state switching according tothe TCI state switching pattern and the TCI state switching periodindicated in the configuration message; and receive a downlinktransmission during at least one of the plurality of TTIs of the TCIstate switching pattern.
 29. An apparatus for wireless communication ata base station, comprising: a processor; memory in electroniccommunication with the processor; and instructions stored in the memoryand executable by the processor to cause the apparatus to: identify atransmission configuration indicator (TCI) state switching pattern and aTCI state switching period, the TCI state switching period indicating anumber of a plurality of transmission time intervals (TTIs), and the TCIstate switching pattern indicating a TCI state for each of the pluralityof TTIs; transmit, to a user equipment (UE), a configuration messageindicating the identified TCI state switching pattern and the identifiedTCI state switching period; and transmit a downlink transmission to theUE during at least one of the plurality of TTIs according to the TCIstate switching pattern and the TCI state switching period indicated inthe configuration message.